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wallrat
5-Dec-2012, 13:50
Hi all, I ordered a pair or cheap magnifiers from Amazon for $3 / pr. Upon receiving them I immediately shattered the holder and ripped the lenses out. They are glass and fair quality. I'm going to mount them in pvc barrels. I've seen others do this. I know how to find the rough focal length and then calculate the aperture, but I was curious if anyone has any other experiences they would share. I've seen some really cool images made this way and I'll enjoy the ride. I'm sorry the attached image is crap but it's tough to capture lenses with a cell phone :)

As for a lens board, I have done mat board before but it seems to fray fast and fall apart. I was thinking about going to Tap Plastics and seeing what it would cost to have a solid black plastic lens board made. Anyone attempted that?

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By the way, here is the product link. It's part of Amazon's new "Add On" program. The nice thing about these is that there were fragile plastic retaining rings that were very easy to remove without damaging the lenses, although it did destroy the retaining ring as planned.

http://www.amazon.com/gp/product/B0019IIOAU

Thanks and Happy Holiday's to everyone!!
-Bill

domaz
5-Dec-2012, 15:13
As long as your on Amazon the book "Primitive Photography" has a section on making "primitive" lenses of historical designs. It goes into a good bit of detail on it. As far as making plastic lensboards Ponoko.com can laser cut Delrin black plastic according to your specs which you lay out in a vector file (made using Inkscape or Illustrator). Their prices are pretty reasonable but their available materials are kind of limiting.

wallrat
5-Dec-2012, 15:50
Thanks for the Delrin link. I was able to get 10 ABS plastic Technika sized boards cut for $10 from TapPlastics then I can drill them at will. I have that book and have read it and literally dozens of others. I have a good grasp on lens design but I'm not going for that, I'm playing with "found" lenses to find the unexpected results. I'll check out Ponoko.com. I'm always looking for more DIY suppliers, thanks!

Andrew O'Neill
5-Dec-2012, 16:09
I got a couple of magnifying glasses from local dollar store. One has a focal length of 300mm, and the other 120mm. Can't remember the f/stops... I have them written down on the boards. I used puddy to seal them in wooden boards. I used 1/8th in pressed board. Black piece of construction paper is my shutter. Very diffused image. Sharpness is increased by taping small apetures in front, again using black construction paper.

wallrat
5-Dec-2012, 17:06
Awesome, I'm hoping for a similar result. I had some ABS plastic lens boards cut that I'll glue a bit of black construction paper to in order to cut reflections. I was going to drill them, mount these lenses in a pvc bushing and glue it to the board. I have $1 in each board so cost isn't a worry. Assuming I have any luck I'll post some images :) It's nice to hear you had some luck. As long as we enjoy the process we get something out of it.

Tim Meisburger
5-Dec-2012, 20:07
I took a plastic magnifying glass and taped it to the front of a copal three shutter (with the normal cells removed) and it made some funky soft images. Have fun!

Jim Graves
8-Dec-2012, 11:51
Here is a link to one of the earlier threads on this forum ... includes quite a few shots with this exact same lens set: LINK (http://www.largeformatphotography.info/forum/showthread.php?35097-A-new-line-of-Chinese-pictorial-lenses!&highlight=magnifying)

The larger of the two ... at least in my examples ... has a 290 mm FL and a very large illumination circle ... easily covers 8x10 ... but the image softens very quickly as you move out from the center. The 290 mm lens works well on 5x7 ... is pretty funky on Whole Plate and gets very "smushy" on 8x10. With a diameter of 86 mm it calculates out to about an f-3.4.

The smaller one has a 55mm diameter, an FL of 220 mm, and is f-4.0.

I didn't take the lenses out of the ring ... I simply sawed off the handle. That left a holder for the lens that could easily be glued right into the lens board hole.

Here is a picture of the small lens on a standard metal 4x5 Speed Graphic lens board ... and a portrait of my son taken with it (click on image to "supersize").

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wallrat
9-Dec-2012, 09:55
Thanks Jim, that is promising. I removed the rings because I didn't trust the, they were really loose in package. I simply used a pvc coupler and a bushing. I'll hopefully shoot with them next weekend and post some images. I really appreciate the technical details. I calculated the larger one at around 245mm so we are pretty close.