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DIY Portable 12 Volt Power Pack

falcoln0014 — Sun, 24 Apr 2011 06:38:39 +0000

Finding a dependable and affordable power source on the go Isn’t always an easy thing to do. That’s why we decided to build one after checking out the pre-built options available. The intended purpose is to power a few under water fishing LED lights and above ground LED spotlights. We will mostly likely be using this to provide power to our camera crane in the near future. Images of project follow the post.

First, let’s define portable. Something that fits into your pocket is nice, but won’t provide the power you need for an all night fishing trip. For this reason we decided to use a Marine Everstart 24DC-6 12-volt battery. The battery is installed in a larger Snap Top box designed for batteries in the group range of 24-31. The slightly larger box gives us plenty of room to fit four 12v outlets, a power switch, and have storage within. It is a bit on the heavy side, but will easily fit into a fishing cart, or on a dolly.

The items we plan on powering with the power pack are two Harbor Freight Mini-Led Spotlights with Magnetic Base (part number 95799), and in the future two AquaStar LED fish lights. Currently we only have funds on this project to purchase one fishing light and it will be here in a few days.

Power draw is very important on a portable pack, so component selection is crucial. We have estimated the Mini-Led spotlights to draw around .34 Amp Hour (assuming 20mA draw for each LED) and the fish lights are rated at .96Ah. The specific lights we chose are located here. We also considered these at Reel Lites, but the AquaStar is a more compact product with higher light output. The only thing that could really be improved is offering a 30 foot cord on the smaller AquaStar model. We almost went with the Reel Lites for that reason alone, not to say one couldn’t solder and water seal on a longer cord. Two spotlights and two fishing lights will draw around 2.6Ah and would totally drain the battery in around 28 hours.

It’s better for the battery if you don’t run it under 50% power, so if you fished for 8 hours in a night (which is quite a bit) and charged it the next day you should theoretically never get below 50%. This might give reason to eventually upgrade to a set of Magnum LED fishing lights. Now, we will go over some photos of the build.

This shows our prototype wiring with two sockets and a lighted toggle switch.

For the switch we simply scratched out a hole using the included mounting plate as a guide. After cutting the hole, the switch pops in easily. For the two 12v sockets we again used the mounting plate as a guide and then used an Harbor Freight 7/8 step bit to cut perfect circles.

Here you can see the battery and internal storage.

This photo shows the battery pack running the mini spotlights.

Here is a shot of the four 12v outlets on the box. We decided to go with four for future expansion. A fifth could easily be added.

All of the connections, including the ones under wire nuts, are soldered for a better connection. The only exception is the hot connection to the 12v sockets. We were going to bypass soldering the grounds to the sockets, but the connector style they use has a tendency to come apart easily.

You can see the storage compartment in the photo here. The smaller fishing lights should also fit, but we’ll see after they come in Monday or Tuesday. Expect an update to this post soon.

Polaroid J66 to J610 120 Fully Manual Camera

falcoln0014 — Sun, 11 Apr 2010 07:40:48 +0000

This article covers the conversion of a Polaroid J66 we picked up at a local flea market into the J610. First was a conversion to use 120 medium format roll film followed by a full manual conversion. All of the research found online says you can’t make the J66 or J33 into a manual camera, but that’s not true at all.

***Update***

We’ve taken some photos with the new setup and will be posting them as soon as the film is dry enough to scan. Of the two rolls we shot one of them turned out perfect. The first roll had some light leaks and didn’t feed correctly because we forgot to pack the spool holder. In order to fix the light leaks we packed some felt scraps around the bellows where they come out of the camera body. Apparently light was still making it past the sewn felt cover.

Click the image below to see samples from this camera. The first shot of Arvest was taken with Fujifilm Neopan Acros 100 and the remainder were Fujifilm Neopan 400 Professional. We’ll be taking more photos in the near future using a mix of Ilford and ADOX films.

This camera was from one of the local flea markets for 6.50 in the Polaroid leather case. According to Land List the J66 is a common Polaroid produced from 1961 to 1963 with a 114mm f/19 meniscus (single-element) plastic lens. The shutter is a pneumatic rotary system rated at 1/15 to 1/1000. Upon noticing a rattling noise and opening it up this negative (converted to positive) was still inside the camera. It’s most likely the last image this camera ever shot for the previous owner.

That being said one of the first things we did after the 120 conversion was attempt to shoot some film. The following photos are two examples. First we have Nathan Crain of Nathan Crain Photography. You can see some light leaks on the right from pin holes in the bellows. The second photo is of Sarah Walter (soon to be Sarah Latus) and Robert Latus. The cropping is a bit off, but you get a general idea of what a photo would look like without leaks. All we did to fix the bellows leaks was wrap the bellows with black felt. Later we came back and made a sewn form fitted stretch cover out of black felt. It may not be fancy, but it keeps the light out.

As you can see the images are quite long (or wide) at about 6×10.5 in negative size. Some people seem to like a 6×6 frame to get more shots and uniform images, but we just wanted the largest images possible. They are border-less, so you’ll want to crop the edges down a bit if you want them to be clean. Next up we’re going to take a look at the simple 120 conversion that we like to call the J610 due to the 6 by roughly 10 negative it produces.

The advance lever we ended up going with (after several failures) is a 1/4-20 Thumb Screw seated directly into the top of an empty plastic 120 cassette. Once you crank it down in there it’s not going to budge, but you’ll need to open the camera up in a darkroom to pull the film off the cassette after exposure. The bottom of the 120 cassette spins freely on a #10-32 bolt held into the body with a nut. On the left hand side where you advance the film from, we simply cut the old spool holder (held in by two small screws) off toward the bottom and put it back together with some electrical tape. A #10-32 bolt goes in from the top and bottom with a nut on each respectively. The tape and pulling the bolts back a bit allows you to easily feed in a fresh roll of 120. As for exposure we’ve figured out you can line up the arrow that goes from top to bottom to the far right. Advance the cassette and place the arrow directly over the right hand edge (to the left of the cassette you’re feeding it into). Closing the camera and crank the advance knob 5 full turns should put you into the first frame. After that advancing 2 and a half (2.5) turns should put you on the next frame. Advance it 2.75 if you’re paranoid about cutting into the last image.

Next up is how we managed to turn it into a fully manual camera. At first we simply wanted to replace the selenium cell with solar cells and a potentiometer to adjust ISO, but that didn’t work out very well. This process requires removal of the front of the camera. Once the bellows are extended you have to remove 3 screws from the back and once that comes off another 4 from the back of the lens assembly to split it in half. One of the 4 screws is the lever that locks your shutter into place when you cock it. It has a spring on it, but the spring is attached.

Once inside disconnect the red and black (or two wires if you have different colors) wires from the selenium cell. We don’t want it interfering with our new manual controls. At this point you’ll want to CAREFULLY bend the orange needle and the little meter bar so that the needle catches in the grooves on the bar. We have ours setup so you barely push it back to disengage and move from notch to notch. Each notch is a different shutter speed at F19 (providing you don’t use the front ring to darken it more). KEEP IN MIND that you can’t move the needle *unless* the shutter is cocked. Trying to do so will most likely BREAK IT. Now, put your camera back together and read on.

As you can see in the photo directly above this, the meter has notches in it that we have taken the liberty of measuring for you. Keep in mind that your mileage may vary, as your shutter may be faster or slower than the one in our J610. To test the shutter speed we placed a solar panel from a $1 LeWorld Dual Power Calculator (from Wal-Mart) on the end of a broken mono audio cable. Positive goes to the center and negatives goes to the outside ground sheath. What you do then is place the solar cell inside your camera up against the back of the lens facing out. You plug the cable into the sound card of your computer to record the wave that it makes when light passes through the shutter. We used a 4 AA flashlight placed directly in front of the lens to create our light source.

This a very low tech approach, but as you see in the photo above you get a wave in the noise as light passes through the shutter. This specific image is from having the needle positioned all the way to the left (maximum shutter speed). Pulling into a program that shows more decimal places yields .0025 for the selected wave, which comes out to about 1/400 for a shutter speed. We believe the needle could be moved further, but would require greater modification than simply cutting out some plastic and bending a few things. You may also want to bend the end up on the arm you lock the needle into. We found the needle had a tendency to stick on the far left and be rather hard to dislodge.

The following is a list of speeds we registered from our J610 from left to right looking directly down on the camera from the top and behind it. (as seen above):

Position – MS time – Estimated Shutter Speed

1 – .0025 – 1/400

2 – .003 – 1/320

3 – .006 – 1/160

4 – .018 – 1/60

5 – .019 – 1/50

6 – .028 – 1/30

7 – .042 – 1/10

These are very usable speeds for most photography and allow the camera to be used at nearly any ISO you would want. We’ll also be posting our shutter speed cross-reference charts in the near future that we use on shoots. Using the charts you can quickly cross reference your digital camera meter reading to acquire an EV rating for your Polaroid (or any vintage camera). Once you have that it’s easy to find the correct shutter speed for proper exposure.

Also on a side note the shutter sensitivity can be adjusted by messing with the bracket on the left hand side of the camera. You can unscrew it, push it up a bit, and tighten it back down for a hair trigger.

Did you like this camera hack? Hate it? Don’t really know what to think about it? Leave a comment below.

WordPress Comments

falcoln0014 — Mon, 08 Feb 2010 21:03:11 +0000

This is a short tutorial on moderating your WordPress comments.

When you log in to WordPress you’ll notice it says Comments, Approved, Pending, and Spam near the center of the screen. Click Comments to continue.

Whenever someone makes a comment it goes into the queue for approval. If you don’t have any pending comments don’t fret, you’ll get some soon enough!. You’ll notice the post at the top is a light yellow color, because it hasn’t been approved yet. Clicking Approve allows web users to see that specific comment on your post. The right hand column shows which post the comment belongs to. Next click Spam to see what has been caught in the spam queue.

This is where anything that the spam filter catches goes. You may or may not have any spam at this point, but as you post more you’ll get more spam. Sometimes the spam filter catches something that isn’t spam (which happens if someone tries to post more than a few HTML links in their comment). If this is the case you can approve the comment just like you would any other comment. When you want to remove all of your spam you can click the check box next to Author, select Delete Permanently from the drop box and hit Apply.

That’s about all there is to know about comments, so I hope it helps.

WordPress Crash Course

falcoln0014 — Mon, 08 Feb 2010 05:15:36 +0000

This is a pictorial guide on how to create a basic WordPress post. It covers tags, categories, photos, and more.

You can click any of the pictures in this article to see them in larger detail. Simply click ‘back’ in your browser to return to the article.

Open the site where your blog is located and click Log in. If your web administrator has not setup the menu to include a ‘Log in’ link and other Meta data you may want ask them about doing it, or about getting a direct link to the admin area.

Enter your username, password, and click Log In to continue.

Click New Post at the top of the screen.

This the Add New Post page, where you can add a title, content, tags, and categories to your posts. Enter a title in the box at the top. Enter your post content into the larger white box in the center. For this specific WordPress install enter words into the Post Tags box automatically plugs them into the articles keywords. Keywords are used by search engines to categorize and place your posts. Keywords should go along with whatever the content of your article is. For example if you were writing an article on baking bread you might have keywords like this: flour, baking, bread, bread yeast, brown sugar. Each phrase is separated by a comma. Entering some phrases separated by commas and clicking add will add the keywords to your article. If you blog about similar content you can click Choose from the most used tags in Post Tags and it will display your most common tags. Tags you use more often will appear in a larger font. Click any of the words or phrases to add them to your post.

The menu highlighted as 1 to 9 allows you to format your blog post. The following list explains each button by number.

1. Bold – Highlight some text and click the B to make your text bold.

2. Italic – Highlight some text and click the I to make some text Italic.

3. Strike Through – Highlight some text and click the ABC to Strike Through the text.

4. Unordered List – Creates an unordered bullet list.

5. Ordered List – Creates an ordered numbered list.

6. Blockquote – Select some text and click “ to create a Blockquote.

7. Align Left – Select some text and click to align it to the left.

8. Align Center – Select some text and click to align it to the center.

9. Align Right – Select some text and click to align it to the right.

A red zig zag under something you typed is telling you that your word is most likely not spelled correctly. Right click it for suggestions.

1. Add an Image – Click to add an image.

2. Add Video – Click to add video.

3. Add Audio – Click to add audio.

4. Add Media – Click to add media.

5. Insert Link – Highlight some text and click this to add a link. It will ask for the URL, target (like the same page, a new page, etc), and title.

6. Unlink – Select text that currently has a link assigned to it and click this button to remove it.

7. More – This is used to hide the bulk of your article from the main page of your blog. I usually write a short introduction and possibly add a photo before clicking the More button. Anything below the More tag can be read from the main page by clicking the article itself or by clicking Read the rest of this entry »

8. Spell Check – Click to check the spelling of your post.

This portion covers adding a photo to your post. Click the spot in your article where you would like to add the photo and then click menu item 1 Add an Image.

Select the image you would like to add from your computer and click Open to continue.

Enter an Image Title, Alternate Text, Caption, and Description. I usually skip the caption, because the caption code isn’t currently XHTML compatible as of this post.

The default settings are fine, so click Insert into Post. If you would like to change the way text wraps around your image you can click one of the options such as Left. The text will then wrap around your photo as indicated on the thumbnail. I would recommend the default of none to start with.

If all went well you should see your image in the post now.

Scroll down the page a bit to see the Categories box. Categories help you categorize your posts into categories and subcategories. Click Add New Category and enter something such as Art. Click Add.

Select your previous category from the drop box and type a subcategory into the box above it. Click add.

You can now see your category and subcategory in the box above. Any category or subcategory with a check box will be selected for the article you are creating. You can even make subcategories on top of subcategories if you wish.

In the top left Posts menu you will see Categories. Click it to open the Categories editor. Here is where you move, edit, and delete categories if you make any mistakes from the Post Editor.

Click Edit under the Posts menu to see all of the posts and drafts you currently have on the site. If you have multiple blog users you can see who created each article under the Author category. Categories, Tags, and the number of Comments on each article can also be seen from here.

This is the end of the crash course on making a WordPress post. I’ll be posting more advanced articles shortly, like how to use HTML to style your post.

Epson Perfection 4490 Photo Scanner

falcoln0014 — Sun, 20 Apr 2008 05:35:35 +0000

This is a review of the Epson Perfection 4490 photo scanner. Now with more tips and tricks.

This scanner is awesome, with a few minor exceptions. It does up to 4800 by 9600 DPI as well as scans in 35mm or medium format slides and negatives. As you can see from the photos, it has a removable white cover that you can insert when you want to scan something other than negatives.

From the photo on the left you can see the various front panel functions of the 4490. The right photo shows the adapter plates for film negatives and slides. The scanner comes with two: one for 35mm and one for 120mm medium format. While I have yet to try the 120mm adapter, the 35mm works great. You can insert two negative strips at once and the scanner software automatically picks up each negative as a different photo. You can also do some basic editing to and pick which negatives you wish to scan in, so you don’t have to take them blindly. Now, onto something I don’t like, the ICE system.

You can see what the ice system does on the right. It just plain looks bad to me. Perhaps I haven’t figured out how to use it just yet, but I set it for quality instead of speed, so you think it would produce something tolerable. Overall, I really like this scanner. It makes beautiful scans of my negatives that only require minor touchup in photoshop to get rid of things like dust spots or small scratches. Buy one, you won’t regret it!

Updates:

I have tested out the 120 scanner plate quite a bit now. I’ve used it to scan 6×6, 6×9, and even some odd sized negatives. The negatives that come from my J610 are actually close to 6×10.5. The scanner handles all of these sizes just fine, but you’ll want to use it in manual mode. I’ve noticed I can actually dry and scan 120 faster than 35mm without any strange warping/curling on the negatives.

You can see some of my 6×6 samples here.