PDA

View Full Version : 4x Objectives for Variety Photography


ray_parkhurst
02-26-2012, 08:32 AM
I have had good service from my Nikon 4x objective for imaging varieties, but it's hard to recommend such an expensive objective to others without being sure it's actually required to achieve acceptable results. So, I decided to do a shootout of a few low cost 4x objectives to compare with the Nikon and see if any are acceptable for shooting Lincoln Cent varieties.

My subject is actually not a variety (sorry). I chose this coin for its deep toning, as showing color and surface finish qualities are also potentially important for variety shots, though less so than for whole-coin imaging. One complaint I've had about many high magnification systems is they have fairly poor color fidelity, and this is one of the qualities the Nikon objective has that so many others don't. If I can find an objective that gives results reasonably close to the Nikon for sharpness and color, and is a lot less expensive, I'll have something I can recommend.

Test setup is the same as for whole-coin photography. Camera is my new T2i, which by the way has now proven itself with this shootout as the choice BY FAR for any work above 1:1. If you knew the lengths I went through to get clean shots with the Nikon D7000 at 4x, versus virtually zero additional effort with the Canon, you would agree.

Modified B&L microscope A-Stand, modified Vivitar bellows, and adapters. Lighting by diffused Jansjos.

Here are the 4X images. These were downsized from original 5184x3456 to 1296x864 (4x reduction) and then cropped a bit down to 1125x750 in order to compensate for framing differences between the shots. Magnification is not quite the same, though bellows extension is identical. All are rated 4x but the rating is apparently not that precise.

Please let me know your feedback on this comparison. I have my own opinion but would like to hear from others to see if we're on the same page...Ray

PS: sorry for the large images, I figured cropping to 1125 wide might help also with the "images too large" complaints

Nikon
http://i943.photobucket.com/albums/ad273/rparkhurst/4x20Nikon20Plan.jpg

Achromat
http://i943.photobucket.com/albums/ad273/rparkhurst/4x20Achromat.jpg

Plan Achromat
http://i943.photobucket.com/albums/ad273/rparkhurst/4x20Plan20Achro.jpg

Semi-Plan
http://i943.photobucket.com/albums/ad273/rparkhurst/4x20Semi20Plan.jpg
Antiquity
02-26-2012, 08:49 AM
Im gonna have to take some photography classes or something, you got some skills I can only hope to emulate.
coinman2009
02-26-2012, 09:06 AM
Way over my head, but watching and learning! Thanks for the photo teachings!
ray_parkhurst
02-26-2012, 09:28 AM
Im gonna have to take some photography classes or something, you got some skills I can only hope to emulate.

There are no classes I know of that will teach you how to do this, but it's actually not all that hard. It is also far easier now that I'm using the T2i than before with the D7000 so should be much more accessible...Ray
Coppertop
02-26-2012, 09:57 AM
Ray I think you should start a coin photography business or something.
ray_parkhurst
02-26-2012, 10:07 AM
Ray I think you should start a coin photography business or something.

Maybe when I retire from the day job. A business isn't as fun as a hobby. I learned that when I turned one of my hobbies into my current day job, but unless you are born with the proverbial silver spoon you've got to make a living. I just don't want to ruin another hobby by bringing in the business aspects.

That said, I've built custom setups like I have been showing here for several folks, though I have not been charging much over what I paid for the components. I've also taken some coins in for photos, but I don't think I'll ever want to go "pro"...Ray
ray_parkhurst
02-26-2012, 10:13 AM
So...any opinions? I have to admit they are all pretty similar, which was not expected. Part of the reason is that I'm using an APS-C sensor, so this reduces the requirements of the lens compared with FF sensors. This is a big advantage for those of us who can't afford the luxury of a FF camera, since we can use less expensive glass that may not be sharp at the edges of the FF frame but are acceptably sharp across the APS-C frame present on consumer and "pro-sumer" cameras. But again, opinions on the comparison please...Ray
Wheat Cents
02-26-2012, 10:14 AM
Very Nice Ray
eaxtellcoin
02-26-2012, 10:30 AM
Ray, Pic #2 has the best definition. I.E. color with the natural contrast. The focus is better also. The lighting on the lower serif is black or dark and that has always been my problem with RPM pics also. Eric
ray_parkhurst
02-26-2012, 10:40 AM
Ray, Pic #2 has the best definition. I.E. color with the natural contrast. The focus is better also. The lighting on the lower serif is black or dark and that has always been my problem with RPM pics also. Eric

Eric...it all comes down to the lighting. These were side-lit with the Jansjos to emphasize surface texture. I've built what I call Directors of various sizes and shapes to get light in where it's needed for illuminating RPMs to best advantage, and can show folks if they are interested how to integrate Directors into their setups. This is another area you will NOT learn in a class! The Directors by definition have to be home-made, so you'll need to get out your paper, tape and scissors and remember your grade school craft skills, but the end result is worth the effort.

Now back to the selection...I agree with you!! It's amazing to me that the modest, "no-name" 4x Achromat is giving results nearly as good in most areas and better in some compared with the Nikon. What's even more amazing is the price difference...the Nikon is a $400 lens (used). The no-name Achromat cost me ........... drum roll please ............... $24.95 NEW !!! That is cheaper than the adapter required to mount it in the setup. Simply amazing...Ray
eaxtellcoin
02-26-2012, 10:49 AM
Not a bad idea, I may try to build an L shaped out of index cards to see if I can back light the top of the coin. I usually shoot strait through
the lens of the microscope and tilt the camera to get lighting correct. I use a Fuji fine pix zoom and a Baush and Lomb with a defused mighty bright from the book store.
copperlover
02-26-2012, 10:59 AM
Very clear pics Ray and it sounds great that the lower cost lens can produce this quality result. Thanks for sharing. I'm loving it.

Lucien
eaxtellcoin
02-26-2012, 11:01 AM
That is not a bad idea.... I'm going to try to shoot some pics with two pieces of an index card, taped across each other to make a folded "L" shape. See if it helps the back side of the coin where the lighting is dark...
ray_parkhurst
02-26-2012, 11:04 AM
That is not a bad idea.... I'm going to try to shoot some pics with two pieces of an index card, taped across each other to make a folded "L" shape. See if it helps the back side of the coin where the lighting is dark...

Just don't attach the card too low so that you get too much side-lighting. Keep it high enough so the reflected light is at most 45-deg to the coin surface. Too low and it will cause you contrast problems, making it harder to see the details...Ray