IRIX 150 macro vs D-FA 100 WR macro ?

biz-engineer · 06-23-2019, 02:09 AM

Originally posted by stevebrot

Did you notice @Luftluss stuff a few posts above?

Yes, I've read all comments / posts, looked at the exif info.

In the meantime I've tried again my closeup lens on the D-FA 70-200, then found some adapter rings for the D-FA 28-105, works well on the D-FA28-105 @ 105. On the 70-200 the working distance is larger but the range of camera-subject distance for focusing is narrow and DoF is so thin. Made an experiment with a coin as subject , used the Pentax commander program, captured about 30 exposure with pixel shift and stacked them with helicon focus, the result is amazing. So the primary problem with the close up lens and 200mm isn't primarily a sharpness problem it is that the depth of field on FF + closeup lens is hardly usable with a single exposure. Getting an old MF lens is actually a cost effective option, the KIRON 105 seems pretty good and it has an aperture ring, can be used with cheap extension tubes.

**Rondec** · 06-23-2019, 02:40 AM

Originally posted by swanlefitte

I am not sure why macro and af is soo looked down on. With my sigma 70 it is extremely accurate. I prefer to use it and allow my left hand to really stabilize the camera because of the weird angles I have to be for most "in the wild" macro shots. My flash is also off balance for position. Just breathing and pushing the shutter can move the focus extremely in macro.

I think a lot of people manually focus to the magnification they want and then move in and out to get the item that they are photographing in focus. There is no right or wrong, but many macro lenses have long focus throws and if they don't have a focus limiter (the DFA 100 macro WR doesn't) then you can end up racking the focus from end to end several times in the process of auto focusing.

biz-engineer · 06-23-2019, 03:18 AM

Originally posted by Rondec

I think a lot of people manually focus to the magnification they want and then move in and out to get the item that they are photographing in focus

It depends what we want to photograph. If I'm at home for doing product photographs, I can setup the system to best magnification manually, move the camera lens to closest distance, tweak for perfect focus , best aperture... If I'm out doing landscape and I see plenty of butterflies, the kind of at home macro setup is too slow, an auto-focus macro lens saves time.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Size comparison: Pentax D-FA 100 WR macro vs. FA 100 macro	Ash	Pentax SLR Lens Discussion	60	02-19-2019 03:08 AM
For Sale - Sold: Irix 15mm f/2.4 Blackstone with Irix 100mm filter holder and Light pollution filter	valimyr	Sold Items	3	10-26-2018 03:17 PM
Experiences with IRIX filter holder IFH-100 and IRIX 100/100x150-Filters?	acoufap	Pentax Camera and Field Accessories	1	10-23-2018 12:10 PM
Ultra wide angle Irix 15mm or Irix 11mm	matroxication	Pentax K-1 & K-1 II	67	09-19-2018 10:01 PM
Pentax IRIX Blackstone 15mm for the price of the FireFly on IRIX USA Site (475$)	Weevil	Pentax Price Watch	7	11-25-2017 03:51 PM

06-23-2019, 02:09 AM	#16
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,245 Original Poster	Originally posted by stevebrot Did you notice @Luftluss stuff a few posts above? Yes, I've read all comments / posts, looked at the exif info. In the meantime I've tried again my closeup lens on the D-FA 70-200, then found some adapter rings for the D-FA 28-105, works well on the D-FA28-105 @ 105. On the 70-200 the working distance is larger but the range of camera-subject distance for focusing is narrow and DoF is so thin. Made an experiment with a coin as subject , used the Pentax commander program, captured about 30 exposure with pixel shift and stacked them with helicon focus, the result is amazing. So the primary problem with the close up lens and 200mm isn't primarily a sharpness problem it is that the depth of field on FF + closeup lens is hardly usable with a single exposure. Getting an old MF lens is actually a cost effective option, the KIRON 105 seems pretty good and it has an aperture ring, can be used with cheap extension tubes.

06-23-2019, 02:40 AM	#17
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 27,663	Originally posted by swanlefitte I am not sure why macro and af is soo looked down on. With my sigma 70 it is extremely accurate. I prefer to use it and allow my left hand to really stabilize the camera because of the weird angles I have to be for most "in the wild" macro shots. My flash is also off balance for position. Just breathing and pushing the shutter can move the focus extremely in macro. I think a lot of people manually focus to the magnification they want and then move in and out to get the item that they are photographing in focus. There is no right or wrong, but many macro lenses have long focus throws and if they don't have a focus limiter (the DFA 100 macro WR doesn't) then you can end up racking the focus from end to end several times in the process of auto focusing.

06-23-2019, 03:18 AM	#18
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,245 Original Poster	Originally posted by Rondec I think a lot of people manually focus to the magnification they want and then move in and out to get the item that they are photographing in focus It depends what we want to photograph. If I'm at home for doing product photographs, I can setup the system to best magnification manually, move the camera lens to closest distance, tweak for perfect focus , best aperture... If I'm out doing landscape and I see plenty of butterflies, the kind of at home macro setup is too slow, an auto-focus macro lens saves time.