| Author |
 Replies: 91 / Views: 14,610 |
|
Pillar of the Community
United States
1314 Posts |
Novice needs advice on holding the camera for coin shots.
I got the camera, a Pentax K-x. I won't master it in 10 years, but I should be able to take good coin shots in much less time.
I got the lens. A Sigma Macro f=50mm.
Before I learn about the rest, (lighting, settings, and processing,) I must decide on my tripod or copy stand.
I can buy a tripod, or build a stand, BUT...
Will the camera body withstand the stresses of verticle use mounted solely by the tripod socket?
It sure looks like a weak arrangement, intended for horizontal shooting.
If I'm going to make a copy stand, maybe I should support the camera by it's body and not just 3 threads of 1/4" ?
The question is about the strength of the camera body and tripod socket, not about the ease of manufacture of a quality stand.
I don't want to strip the socket out of a heavy camera while using a heavy lens.
I got a few good ideas from some locked topics.
All input is appreciated.
Thanks,
Kurt
|
|
|
|
Moderator
 United States
23522 Posts |
Quote:
I don't want to strip the socket out of a heavy camera while using a heavy lens. I solved that worry very easily by buying a tripod so cheap that it would fall apart far sooner than the socket would strip. So far, so good. My $20 tripod holds a dSLR w/100mm Macro lens, no problem. The disadvantage of a tripod is getting a nice viewing area - I weight a relatively narrow (~8") board on one end and dangle it away from a table under the tripod. A table corner will work in a pinch. *Any* tripod is built for that weight. Copystands, not so much. Building your own copystand is not a great engineering achievement in and of itself, but easy height adjustability while retaining a perfectly perpendicular camera is tougher than it looks. I know of guys who have adopted drill presses to the task. |
|
Pillar of the Community
United States
4038 Posts |
Quote:
Building your own copystand is not a great engineering achievement in and of itself, but easy height adjustability while retaining a perfectly perpendicular camera is tougher than it looks. I know of guys who have adopted drill presses to the task. Or Microscope stands... Many copy stands I've seen are pretty rickety. The key is to hold the camera, or more specifically the objective end of the lens, perfectly still relative to the coin during shooting. This is hard to do with a tripod unless it is solidly attached to the surface the coin is on, and even then mounting to the camera body allows the lens to move relative to the coin. It does not take much movement to screw up a shot. You can make a tripod work but you have to be careful to keep everything solid. The stands I build are extremely solid, but I've tried mounting my camera directly to the stand with my 105VR Micro mounted and the vibration level was unacceptable. The only way I was able to get a clear shot was by wedging chunks of sorbothane rubber blocks between the lens and the stand to reduce the vibration. I have a Leica BOOWU system that I've been wanting to try. Basically a lens holder with legs. Pentax made a similar one. This is the classic "copy" method that holds the lens perfectly stable on the surface that the document would sit on. Should work perfectly well for coins, but of course all the distances have to be adjusted to get correct magnifications, etc. So bottom line, figure out a system (tripod, copy stand, whatever) that holds the lens as stable versus the coin as possible, and you will get good shots. If you can tap the coin surface, or the camera, and the image bounces around much and/or doesn't damp out very quickly, you will have issues with clarity of your shots. Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
|
Pillar of the Community
United States
4038 Posts |
By the way, if you support the lens the way I am describing, by putting pressure on it with sorbothane or similar material wedged between lens and tripod or stand, it relieves the torque placed on the camera mount due to the camera weight. In fact, it will end up putting more reverse torque on the mount than forward! ...Ray
|
|
Moderator
United States
23522 Posts |
I'm forced to wonder about the sensitivity of Nikon stuff, Ray. All it's ever been for me was, "throw it on the tripod, lock the rings and go shooting." Even handheld, at f/2.8....  |
|
Pillar of the Community
United States
4038 Posts |
Maybe I'm just over-sensitive to small amounts of movement that can only be seen at 1:1. Or maybe Nikon stuff IS more sensitive! All I know is that during all my lens testing, I had to bolt things down in order to be able to make effective comparisons that were not marred by movements. And even when I bolt things down as much as I think is possible, any lenses over 100mm start to show effects due to the longer working distance amplifying the effects of movements. The shot you show here may be at too low a magnification (I think, unless those clover leaves are really small), and definitely too low a published resolution, to show the effects I am talking about. I'm worrying about mags around 1:1, at 100% pixel detail. Here's a shot of my 1921 Morgan dollar at 1:1, with a 100% pixel detail of the bottom cornflower:   I am doubtful this can be done handheld. If so, then I guess I really need to shift over to the Canon camp to take advantage of EFSC! Ray |
|
Moderator
United States
23522 Posts |
Um, no, I doubt that can be done handheld.  Below is about the best I could do with my Canon rig in terms of magnification; I was deliberately pushing the lens closer than spec to maximize magnification. I chose a similar "pose" to help the discussion. 12MP camera vs 16MP; with a 16MP sensor it would be slightly larger than the image you posted. This is the quick-n-dirty, "throw it on a cheap tripod and shoot" result. The color is accurate; the coin was toned. Unretouched, shot as .jpg, 100% crop, 1/200 & f/10 @ ISO400:  |
|
Pillar of the Community
United States
4038 Posts |
Looks good! Is the f/10 effective at the magnification (looks to be M~0.7, correct?), or what is shown on an aperture ring? My effective aperture was 11.2 (f/5.6 at M=1) and it's already starting to show some diffraction effects. I think the EFSC must make the setup more forgiving, as I'd never get good clarity on tripod with a dangling lens...Ray
|
|
Pillar of the Community
 United States
1314 Posts |
Thanks for the help. As I surmised, the tripod socket is the weakest mount, but the easiest to assemble. And can be done with a garage sale drill press stand. I used a stand that was designed to hold a hand held drill, and converted to a drill press. I used the device for years as a gunsmith. Then retired it as I got newer drill presses for the shop. Original cost was less than $20. and garage sale price should be around $10. The old arrangement is easily converted to a tripod socket mount. And with a little modification, made to cradle the camera body. And with some work, I think I could get it to be a lens support system.    May the spirits help me, as I have never tried to upload a picture before. Newbie crosses fingers and presses send button. Thanks, Kurt |
|
Moderator
United States
23522 Posts |
Heh. That's awesome. Nothing warms my heart more than field engineering. I do not believe you'll need anything more than the socket mount for your kit as it is. Understand, what Ray and I blather on about is wringing the last few tenths of a percentage of performance out of relatively high-end equipment; none of the images you saw us posting are remotely relevant to nice, clear, gradable coin images for posting on a website. Your goal is a sharp, color-correct image where the actual coin diameter is 800px. Anything bigger than that is gravy, until you start shooting for variety details, at which point you're going to want to be upgrading your lens. The equipment you have should satisfy the original goal nicely, and it's sophisticated enough that when/if it becomes unsatisfactory to you and you upgrade, it'll be like buying a much nicer car when you're already an expert driver. Personal preference: I use, almost exclusively, well-worn 100% cotton t-shirts as backgrounds. After a bunch of washings, they're nice, soft surfaces for higher-grade raw coins to rest on. I'd rather worry about a little lint than hairlining from accidental movement on a harder surface. |
|
Pillar of the Community
United States
3076 Posts |
Nothing warms my heart than typing for a half hour for it to go POOF"""Let me say...this that over the past few months we have had so many so much good advice on how to attain nice close up photos AND the "science" behind it... WE are so privaliged to have the members here go beyond just taking a picture to the science behind them.. And the fact they use different equipment and reach for the stars and show us how to reach for them...I can't express more than you have both shown us all and WHY....
|
|
Pillar of the Community
United States
4038 Posts |
That stand is pretty cool. Can't get much more rigid than that. The ultimate test is to hook up to a PC and bump the setup, or the bench, and see if things bounce around while watching at 100% resolution. In this case with such a rigid setup what you will see is how rigid the camera mount itself is. The camera and lens have a lot of mass and the mount is pretty simple and flexible. In spite of SuperDave's good published result I am still a proponent of "more is better" when it comes to rigidity.
Another option with this type of setup is to use a lens mount directly to the stand, such as Nikon's PN-11 mount. I can verify this helps tame vibrations by decoupling the mass of the camera from the lens. Some lenses, especially longer ones, have integrated lens mounts that allow you to mount the lens to the tripod or stand rather than the camera. A few macro lenses, such as the classic "Bokina" and Canon's MPE65, have this feature as well to improve rigidity for high magnification imaging. The same problem that birders have with long telephotos we macro shooters have at high magnifications, it doesn't take much movement to mess things up.
Regarding the background, my favorite is textured plastic. It's soft enough to not scratch the coin surfaces, yet it's still easy to slide the coin around on. TAP plastics or equivalent can cut a piece for you in any color or finish you desire. I had them laminate up a reversible white/black combo, cut in circles to fit the B&L A-Stands I use as basis for my camera mounts. All my recent photos use these as backgrounds. Even though the backgrounds look grey, they are technically "black" plastic. If you go that route, get "black" and it will show up as medium to dark grey in the image.
|
|
Moderator
United States
23522 Posts |
Heck, Ray, more of anything is always better. I have to admit a bit of worry, mounting on just the socket. My 450D/100mm weighed something like 1060g together, with the weight forward since the lens was heavier than the camera. Chute72's Pentax is rather heavier than the 450D (515g vs. 435g) but his lens is considerably lighter, almost 400g lighter than the 100mm f/2.8. A socket-only mount should be fine for him. I further admit that there was "play" in my tripod mounting. It just seemed like the kit was capable of damping any vibrations regardless; a problem I never had to fix. My next camera will be at least 100g heavier, and the additional concentration on magnification means I'm going to have to concentrate more on the mount, even using the Rodenstock instead of the Canon lens. |
|
Pillar of the Community
United States
4038 Posts |
All I can offer for suggestion is to use a good bellows. Since the 75ARD requires adjustable focusing anyway, it benefits from being rigidly mounted on the front standard, effectively decoupling the camera from the lens. So far the best bellows I've found is the (shhh, don't tell anyone else...) Pentax Auto Bellows. It's a similar design to the Nikon PB6 but the Pentax is a lot cheaper, is just as rigid and smooth, and a bit smaller as well. Plus the chrome knobs look better than the PB6's black ones. BTW, have you purchased your 75ARD yet? There is one for sale on ebay right now that claims to be in mint condition. Your setup may not care as much about vibrations due to the EFCS, at least for relatively fast shutter speeds. How well does your setup do at low shutter speeds, <1/10sec? |
|
Pillar of the Community
United States
1314 Posts |
First, My pictures are in the wrong order. It looks like an article of how to build a drill press from a camera stand. But I am so pleased that I got them to post, I just don't mind.
Second, I don't really shoot off a paper plate, but I was working on the kitchen counter, it was handy and I was in a hurry. And I appreciate your suggestions concerning better backgrounds.
Third, everything else is over my head.
I'll learn... But I haven't yet.
I have no idea what a 75ARD is. Or EFCS. How to use a bellows. Or what my camera settings are or should be.
I don't expect to learn it all in one evening, but maybe learn one thing each evening.
It took me one whole evening to get the correct batteries and install them.
Another to load the program onto my computer, etc. (And then discover the software was out of date.)
I don't even know when my camera is in focus. I have been taking a shotgun approach to getting images. I turn the focus ring from slightly blurry to slightly blurry while shooting, hoping to capture the one photo in between that is in focus.
The socket mount is probably the weak link in my mounting system. I've got a 400 lb. desk, and the drill press is beefier than it looks.
Once I get a few test pictures, I'll have an idea of what's wrong, and how to improve it.
And of course, I'll need to read the other 290 pages of the 300 page Owners Manual.
Maybe read some on line articles. Buy a book or two. And practice, practice, practice.
Look for my first picture of a coin soon.
Thanks all,
Kurt
|
|
Pillar of the Community
United States
1314 Posts |
 Should be good enough to determine date position.  Some detail here. I still don't know what I'm doing, but I think I'm doing it better. I have no idea how many pixels these pictures are, but when I right clicked on the picture and clicked properties, I got file size. I kept cutting them down until I got them to 100K. I'm thinking that I will never be able to post a full coin with my current camera settings. And I don't know (yet) what white balance is, but I'm pretty sure I don't have it. Save for another lesson. Thanks, Kurt |
| |
Replies: 91 / Views: 14,610 |
Posted 08/16/2011 12:35 am
