135mm Telephoto Lenses Questions

Main difference between lens focal lengths will be that all your distances get longer as well. The lens needs more extension to get to the same magnification, but at the same time you'll get more working distance. More working distance means more flexibility in getting your lighting in there at the high angles required for good color and luster shots. I've had excellent results from a couple 135mm lenses I've tried, with reasonable extension on the bellows and good working distance. So I think your choice of 135mm is a good one. Many so-called "150mm" or even "180mm" macro lenses shorten their focal length at higher magnifications. So in the end they are more like 135mm or even 120mm lenses when focused close enough for coin photos. This is their "trick" for getting a wide range of magnifications. For a long time my very favorite lens was a 135mm, but when I started using microscope stands I settled on shorter focal length lenses since the stands don't have a whole lot of extension range. As long as your copy stand / tripod setup can handle the extra distance, should work great...Ray

Thanks for your reply's, the extensions term is merely a term when you adjust the lens itself it either moves towards the (back)camera or to the object, (forwards), my thinking its something to do with magnification, as far as f stops are concerned, I am at full open apeture stopped down 2, I did finally get it into focus, at 24 inches, I see that the ISO and the shutter speed play an important factor in the manual mode using a bellows....and my meaning here is, I boosted my ISO 400 and shutter to around 1/80 even see the coin. AS this lens is not supported by the camera it self...from this I was able to get the coin into view at full focus, when I took the shots the were WAY over lighted, After I had the coin in focus, I simply adjusted the live view adjustments back to ISO 100/200 and played with the shutter speeds to find the outcome...the thing is...the results of the shot that pop up in a separate window,,,ARE IN NOW WAY what you see on screen in live view...At this point I can hardly see the coin,,very dark, yet the final shots are spot on.....Knowing the coin was in focus...yet the lighting in live view is back wards from what I see, it just takes a few more shots to choose what worked best...sound familiar? LOL...,
For my question, about the lens if the clearity is better if the lens is extended to full open or retracted to be closest to the camera body,, my battery went dead..
one needs more ammo in a battle LOL....here are my first attempts with this lens....one thing I immeadiately noticed
the color, was really close to the coins perimeter colors
but not quite there for the center...detail is good even when I blow it up....Here are the shots...





I'll try tomorrow to see what happens if I "Zoom" the lens out to its full magnification and see if I can get it into focus and its results...