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07-05-2018, 01:26 PM   #106
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Below:
1) 200mm SMCA + Raynox 150 (=1,5X)
2) 55~300mm @ 300mm + Raynox 150 (=1.5X)

Sorry about the color difference. These are straight from camera JPEGs. Both lenses were @ infinity focus, so closer focusing = greater magnification is possible with either lens. Both shot @ f8.

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07-05-2018, 01:27 PM   #107
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QuoteOriginally posted by UncleVanya Quote
Ok - DA 18-50 with DCR-250
First shot is at minimum focus at 50mm without a close up lens attached.
Second shot is DCR-250 at the same minimum focus still at 50mm (the largest magnification I can get from this combo)
Last shot is lens at infinity focus using the DCR-250 and still at 50mm.

All shot handheld and not intended to be art... just a quick and dirty comparison. The 18-55 will likely give better magnification due to the higher native ratio of close shots already and the slightly longer focal length.
UncleVanya - very solid magnification with 250 on the 50mm...how much working room did you have? And how much focal length?

---------- Post added 07-05-18 at 01:29 PM ----------

QuoteOriginally posted by WPRESTO Quote
Below:
1) 200mm SMCA + Raynox 150 (=1,5X)
2) 55~300mm @ 300mm + Raynox 150 (=1.5X)

Sorry about the color difference. These are straight from camera JPEGs. Both lenses were @ infinity focus, so closer focusing = greater magnification is possible with either lens. Both shot @ f8.
Very cool...that is quite good magnification. How close did you have to get to the bill on each of those shots? Those were using the 150 so I imagine I'd have to get closer with the 250 form what I've read on here.
07-05-2018, 01:36 PM   #108
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QuoteOriginally posted by GoldMountain Quote
Those were using the 150 so I imagine I'd have to get closer with the 250 form what I've read on here.

For both of those shots, the distance was about 8 inches from the front of the lens to the subject because both lenses were set at infinity. If the 250 unit were attached, the distance would have been about 4 inches from the front of the lens to the subject, again, provided the lens is focused at infinity.
07-05-2018, 02:02 PM   #109
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QuoteOriginally posted by WPRESTO Quote
For both of those shots, the distance was about 8 inches from the front of the lens to the subject because both lenses were set at infinity. If the 250 unit were attached, the distance would have been about 4 inches from the front of the lens to the subject, again, provided the lens is focused at infinity.
Apologies for my naivete, but does "focused at infinity" mean?

07-05-2018, 02:42 PM   #110
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QuoteOriginally posted by GoldMountain Quote
UncleVanya - very solid magnification with 250 on the 50mm...how much working room did you have? And how much focal length?
I elected to use minimum focus distance rather than infinity and it was about 4 inches or so if I recall. It could be slightly closer but not closer than 3 inches from the front element.
07-05-2018, 02:55 PM   #111
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I have a M 100/4 Macro with some fungus in it that still works very well. The $75 I paid seemed well worth it.
07-05-2018, 03:17 PM   #112
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QuoteOriginally posted by GoldMountain Quote
Apologies for my naivete, but does "focused at infinity" mean?
The lens attached to your camera can focus from infinity down to somewhere close, three feet, eighteen inches, depending on the lens. The "strength" of a close-up filter is by convention determined by the distance to an in-focus object when the lens attached to the camera is focused at infinity = the farthest away the basic lens can focus. Also by convention, the "strength" of a close up filter is called the "diopter value." To get the distance from the front of a lens to the object that is in focus when a close-up filter is attached AND the lens is focused at infinity, you divide 1,000mm (= one meter) by the diopter value of the close-up filter. So if the diopter value of a close up filter is +1, then when it is attached TO ANY LENS REGARDLESS OF FOCAL LENGTH, an object 1,000mm in front of the lens will be in focus IFTHE LENS IS FOCUSED AT INFINITY. By rotating the focusing ring, you can focus closer, but you cannot farther away. For a +5 diopter close-up filter, the focus distance would be 200mm; for a +0.25, the focus distance would be 4,000mm (= four meters). etc..... The vast majority of close-up filters have diopter values from +1 to +5, but there are some that have higher or lower values. There are some +10 diopter close-up filters, but these are generally plagued by poor IQ in a variety of forms.
07-05-2018, 04:10 PM - 1 Like   #113
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QuoteOriginally posted by stevebrot Quote
Don't taunt the wheatman! The image is a nice illustration of what is easily accomplished with a dedicated macro.


Steve
It worked out. It shows how intent can make a drastic difference in how you go about lighting.
I certainly made the wrong assumption. Wheatfield corrected me. I now think his image is very good.

07-05-2018, 07:33 PM   #114
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QuoteOriginally posted by stevebrot Quote
Don't taunt the wheatman! The image is a nice illustration of what is easily accomplished with a dedicated macro.


Steve
No Steve, it's a valid point. Somewhere I have some 4x5s and possibly 6x7 chromes from my shots for the jewelry company. They are quite different from that illustration photo which was shot with window light. I didn't even use a reflector, which is why it's rather dark on the right side.
As a point of interest, the fabric background is one of the bags that Pentax shipped with LX camera bodies.
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