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04-06-2012, 09:09 AM   #31
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QuoteOriginally posted by RXrenesis8 Quote
This argument only works for subjects/scenes that you are photographing at less than 1:1. Everything smaller will be shot at the minimum working distance, or with some form of extension.
Ok put an extension tube on the FF and 150mm to bring you to the same perspective as a 100mm on apsc and you have the same working distance. Same concept either way.

04-06-2012, 09:37 AM   #32
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QuoteOriginally posted by atlnq9 Quote
Ok put an extension tube on the FF and 150mm to bring you to the same perspective as a 100mm on apsc and you have the same working distance. Same concept either way.

Picking nits, but you can't have both the same perspective on FF and APS-C *and* 1:1 focusing.

Macro on FF is a larger projected image than macro on APS-C.
04-06-2012, 10:29 AM   #33
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QuoteOriginally posted by ElJamoquio Quote
Picking nits, but you can't have both the same perspective on FF and APS-C *and* 1:1 focusing. Macro on FF is a larger projected image than macro on APS-C.
In all other industries involving macro/microscopy nobody talks about there image being 1x. Because as soon as you print your picture it isn't 1x (unless you print at 24mm x 35mm from FF). I am just saying you have the exact same focusing distance when making the exact same picture with a FF camera with 150mm lens focused at 1:1 and apsc with 100mm (lens is obviously focused at less than 1:1).

My initial comment was that the 100mm perspective gives the exact same image as a FF and 150mm.

The poster disagreeing was talking about working distance being different. As I explained getting the same magnification (images printed to the same size with same perspective) it is the exact same working distance.

The discussion was all about my original comment. Not whether the perspective of FF at 1:1 and apsc at 1:1 lens magnification gives the same perspective.

Not whether the 100mm on apsc focused at 1:1 is the same as 150mm on FF focused also at 1:1. Sure the image on the apsc when printed to the same print size as FF and 150mm will have higher magnification regardless of both being focused at 1:1. But you have to understand magnification.

But when comparing the two you have to talk about perspective. Final magnification relies solely on how large you can suitably print. A image from a 645D focused at 0.5x is capable of larger magnification than a picture from a K7 at 1x. Because you can print larger. This is basic logic.

Last edited by atlnq9; 04-06-2012 at 11:21 AM.
04-06-2012, 12:25 PM   #34
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Sure, I think we're all smart enough to understand that, and to understand the differences between DOF and pixel-magnification to print that are entailed with both formats, too.

04-06-2012, 06:14 PM   #35
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QuoteOriginally posted by atlnq9 Quote
you have the exact same focusing distance when making the exact same picture with a FF camera with 150mm lens focused at 1:1 and apsc with 100mm (lens is obviously focused at less than 1:1).
this was taken with a Nikon D3s with the Nikkor 105mm f/2.8 VR lens - I switched the D3s to 5.1mp DX crop mode and then back to full 12mp FX mode.
Both of these images were both taken with the camera on a tripod and the Nikkor 105mm f/2.8G ED VR with the focus fixed at 1:1 magnification.

Last edited by Digitalis; 04-06-2012 at 06:21 PM.
04-06-2012, 06:37 PM   #36
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QuoteOriginally posted by fs999 Quote
A new lens is announced by Sigma : APO Macro 180mm F2.8 EX DG OS HSM.


This is the world's first 180mm macro lens incorporating a magnification ratio of 1:1 and a large maximum
aperture of F2.8.
This a little bit of marketing spin. Sure, it is f2.8 but they discontinued their previous 180mm/3.5 macro in k-mount a couple of years ago and it was a respect 1:1 af macro lens. Plus, Pentax has had a couple of 200mm/4 macro lenses that will be the bench mark for this lens f2.8 maximum aperture or not. The big thing this lens will have going for it if it is released in K-mount will be that it is in production.
04-06-2012, 06:44 PM   #37
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QuoteOriginally posted by atlnq9 Quote
Y. . .

Was the 180 3.5 ever made in a OS version? Could be why they dropped it because with the design it couldn't be implemented. The 150mm and this new 180mm could... .
What happens when OS is used and SR is on? When using a tripod, SR is generally turned off in the Pentax bodies. Is this the case for OS?

QuoteOriginally posted by fs999 Quote
B+H didn't read your post... New Sigma 180mm F2.8 Macro
That was because Sigma USA initially listed the 150mm for Pentax but then removed it. Sigma never released the previous 150mm in Pentax either.
04-06-2012, 06:51 PM   #38
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BTW, FWIW Sigma USA told me that they don't know whether or not this lens will be available for Pentax yet, as the Japanese HQ hasn't sent out any details yet.

The new 105 and 150 macro lenses didn't come out for Pentax, so I'm starting to have my doubts here as well. I wonder why they didn't though, especially the 105mm.


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04-06-2012, 06:53 PM   #39
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QuoteOriginally posted by Adam Quote
BTW, FWIW Sigma USA told me that they don't know whether or not this lens will be available for Pentax yet, as the Japanese HQ hasn't sent out any details yet.

The new 105 and 150 macro lenses didn't come out for Pentax, so I'm starting to have my doubts here as well. I wonder why they didn't though, especially the 105mm.
The Sigma 105 EX DG was a work horse for me before I got the D FA 100mm WR. It was a very good lens and I don't understand why the discontinued it if they weren't going to replace it.
04-06-2012, 07:09 PM   #40
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How about this? Why not new DA lens.

SMC Pentax-FA* 200mm F4 Macro ED [IF] Reviews - FA Prime Lenses - Pentax Lens Reviews & Lens Database
04-06-2012, 07:51 PM   #41
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QuoteOriginally posted by Danny Delcambre Quote
Pentax has been asked about something like a D FA 200/4 ED [IF] WR but they never answered. Of course that was during the Hoya boys tenure. Perhaps Ricoh would better field the idea, but they would probably sell for $8k based on current prices.
04-07-2012, 01:09 AM   #42
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QuoteOriginally posted by Digitalis Quote
this was taken with a Nikon D3s with the Nikkor 105mm f/2.8 VR lens - I switched the D3s to 5.1mp DX crop mode and then back to full 12mp FX mode.
Both of these images were both taken with the camera on a tripod and the Nikkor 105mm f/2.8G ED VR with the focus fixed at 1:1 magnification.
Yes, you have targeted two different magnifications in these two pictures. That was not my argument at all.

See below. Now they are at the same magnification.

Last edited by atlnq9; 04-07-2012 at 01:19 AM.
04-07-2012, 01:14 AM   #43
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I spoke to Sigma a month ago about this lens and the new 150mm. They told me that they will not be made for the Pentax mount.
04-07-2012, 01:14 AM   #44
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QuoteOriginally posted by atlnq9 Quote
Yes, you have targeted two different magnifications in these two pictures. That was not my argument at all
That doesn't sound right. They were both shot at 1:1, both have the correct FoV showing for the sensor size used. They are both at the same magnification, the FF shot is just scaled down a bit more to match the dimensions of the simulated APS-C shot.
04-07-2012, 01:22 AM   #45
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Same magnification now.
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