Cheap macro lens

Azzy · 11-10-2011, 03:39 PM

I'm actually very close in obtaining Tamron 90mm for reasonable price from another member here.
It beat the Lester dine kit that some members recommended as well due to the weight / no AF for other general usage.

Quote:

* For farther work and lotsa mag: Any affordable 90-100-105mm A-type or AF macro lens; 4-6 deglassed 2x TCs.

Quote:

#1: For a non-macro lens, yes. For a macro lens, the MFD doubles. A non-reversed lens cannot focus closer than its focal length.

#2: Light is cut by 2 f-stops. So at 100/2.8 lens with MFD=10cm, with a 2x TC, becomes a 200/5.6mm lens with MFD=200mm.

So Rico, even if I deglass the 2xTC I will cut 2 f-stops ? So the 90mm tammy would become 180mm F4 ? What kind of mag ratio I would obtain on the mfd ? and if the effect is multipled 6 2x TC would = 12:1 mag ?

This deglassed TC option is highly desirable for me since I'll keep farther MFD from the subject

joe.penn · 11-10-2011, 04:03 PM

Originally posted by Azzy

It beat the Lester dine kit that some members recommended

It beat the who kit? Um, not sure where you got that info from - care to share?

--

Azzy · 11-10-2011, 04:09 PM

Originally posted by RioRico

A Lester Dine dental-macro lens with a built-in ringflash. Can't be beat!

from what a gather its pretty much the vivitar 100m s1 macro lens which has quite a cult status in macro world...

joe.penn · 11-10-2011, 04:16 PM

Originally posted by Azzy

from what a gather its pretty much the vivitar 100m s1 macro lens which has quite a cult status in macro world...

The Vivitar S1 2.5 105mm <- Same lens as the 105 2.8 Lester Dine both manufactured by Kiron. The Tammy is a good choice, it is however not as good as the Kiron 105's optically (although you could PP to get better results), it does have the advantage of being AF which may come in handy if shooting other things besides macro.

..

newarts · 11-10-2011, 04:50 PM

Which Tamron 90 are we talking about? 1:1 or 1:2? Is it an "A" type lens?

Here's the effect of adding a de-glassed TC to a 90mm non-IF lens.
20mm thick TC, 1:1 90mm lens; m = (90+90+20)/90 -1 = 1.2x, effective f-stop multiplier ~ 1.2x
20mm thick TC, 1:2 90mm lens; m = (90+45+20)/90 -1 = 0.72x, effective f-stop multiplier ~ 0.72x

30mm thick TC, 1:1 90mm lens; m = (90+90+30)/90 -1 = 1.33x, effective f-stop multiplier ~ 1.33x
30mm thick TC, 1:2 90mm lens; m = (90+45+30) /90- 1 = 0.83x, effective f-stop multiplier ~ 0.83x

Adding a TC behind a lens does NOT change the working distance, and the factor increasing the magnification is the same as the factor increasing f-stop.

That is, if a 2x TC is added behind a lens, working distance does not change but both magnification and f-stop are increased by 2x.

I just tested to make sure this is the case.

RioRico · 11-10-2011, 05:07 PM

Originally posted by newarts

At 1:1 mag the working distance is 2X focal length - in this case, 200mm.

Correction noted and applied. Thanks!

Quote:

Be aware that TC's are often only about 20mm thick so a de-glassed TC won't increase the magnification of a long focal length lens by much.

All four of my PK 2x TCs measure thicker than that. An Albinar M-type and two 2 deglassed A-types (Focal and Promaster) measure 26mm; a Cambron M-type measures 31mm thick.

No, these won't significantly boost magnification of longer glass. They are useful only with a limited subset of lenses. My A-type and AF collection is rather small. One TC on a 28mm lens demands a working distance only about 1in in front of the lens; too close. I can use one or both on the 35-70 and a 50mm. Using both on a 135mm doesn't put me into macro territory; ditto with zooms in the 70-210mm range except at the short end..

joe.penn · 11-10-2011, 05:11 PM

Originally posted by newarts

Which Tamron 90 are we talking about? 1:1 or 1:2?

My experience is with the 90mm SP Di 1:1 and guessing that is the one he is referencing...

--

Azzy · 11-10-2011, 05:44 PM

Yeah its the 90mm macro DI 1:1...so If I understood newarts correctly, to get 2:1 mag on the tamron I would need a 90mm thick ext tube / deglassed TC ? (90+90+90)/90-1 ?

Laurentiu Cristofor · 11-10-2011, 06:01 PM

Originally posted by joe.penn

The Tammy is a good choice, it is however not as good as the Kiron 105's optically

In what ways is the Tamron not as good as the Kiron optically? Any examples showing the difference would be much appreciated.

Azzy · 11-10-2011, 06:10 PM

Originally posted by newarts

.

At 1:1 mag the working distance is 2X focal length - in this case, 200mm.

Be aware that TC's are often only about 20mm thick so a de-glassed TC won't increase the magnification of a long focal length lens by much.

A standard 2X TC behind your Tamron zoom should give about 1:1 magnification.

Finally, the working distance for a Raynox 150 on a 300mm lens focused at infinity (1.4x) isn't bad; about 214mm ~ 8.3" a little more than a 100mm macro lens at 1:1

I didn't know how I missed this post....I thought Raynox working distance is pretty close ~4"
The tamron 90mm MFD is 3.9" or 99mm...so with the raynox it pretty much double the MFD for 1:1 mag!!!!

Is there any reason (aside having AF portrait lens) picking the more expensive 90mm tamron over this combo ?

newarts · 11-10-2011, 06:11 PM

Originally posted by Azzy

Yeah its the 90mm macro DI 1:1...so If I understood newarts correctly, to get 2:1 mag on the tamron I would need a 90mm thick ext tube / deglassed TC ? (90+90+90)/90-1 ?

Yes.

A simpler way (although the image quality might not be as good) is to just use a 2X teleconverter.

newarts · 11-10-2011, 06:29 PM

Originally posted by Azzy

...
Is there any reason (aside having AF portrait lens) picking the more expensive 90mm tamron over this combo ?

Well, the 90mm Tamron might be a little better IQ up to 1:1, but looking at the results people get with the Raynox on a good zoom, the 90mm Tamron cannot be a whole lot better. If the photos will be displayed electronically then I'll bet that any differences will be hard to see.

One drawback of the Raynox route is the edges of the photo won't be as sharp as the center. This makes no practical difference with natural subjects.

It might help you to spend a few minutes looking at the long Raynox Macro Club thread to see what quality to expect: https://www.pentaxforums.com/forums/lens-clubs/74221-raynox-macro-club.html

If you'd like better quality put an el-nikkor 50:2.8 on a bellows for less than $100. Use a glass-less PK/A TC to trick the camera into thinking the bellows is an A type lens. There are other tricks available to fool the camera so the automatic flash will work with an inexpensive bellows.

excanonfd · 11-10-2011, 07:00 PM

Originally posted by Laurentiu Cristofor

In what ways is the Tamron not as good as the Kiron optically? Any examples showing the difference would be much appreciated.

Yup, I am interested too. Please put up some lens resolution test results (no pixie dust or pixie dungs, please!). Meanwhile, I did find this little snippet from this article: Pentax Lens Review by Peter Spiro

Some recent advertisements from Carl Zeiss claim that the Zeiss Planar T 60mm macro lens can resolve 150 lines per mm. Perhaps one should expect no less from a lens that sells at a discount mail order dealer for about US$800. If true, this would give it a higher resolution than any lens ever tested in Modern Photography. The peak I found there was 110 for a 90mm macro by Tamron. Of course, this is the best resolution at the best f/stop for the lens.

Please read the last two sentences from the above paragraph...

Laurentiu Cristofor · 11-11-2011, 12:29 AM

Originally posted by excanonfd

The peak I found there was 110 for a 90mm macro by Tamron.

Was that the adaptall version? Someone had posted old reviews (from Modern Photography maybe?) comparing macro lenses and the 52B came out much better than the VS1 and pretty much anything else. Can't find that post now though.

hoanpham · 11-11-2011, 01:01 AM

Originally posted by excanonfd

Originally posted by Laurentiu Cristofor Quote
In what ways is the Tamron not as good as the Kiron optically? Any examples showing the difference would be much appreciated.
Yup, I am interested too

I have the Tamron 90/2.5 adaptall2 with belonging TCx2, new Tamron90/2.8 AF, new Sigma105/2.8 AF, fujinon55 w belonging tube, pentax M50/4 + tube + pentax TCx2 + pentax TCx1.4, bellow, multiple sets of tubes, tried reverse ring on many of primes - but no Kiron.

I havent try stacking primes, like 20/28/30/50 on 135/150/200.

I though modern optics with AF on the Tamron90/2.8 and the Sigma 105/2.8 should be at least equal the Kiron if not better due to newer coating and such?

11-10-2011, 04:50 PM	#35
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Which Tamron 90 are we talking about? 1:1 or 1:2? Is it an "A" type lens? Here's the effect of adding a de-glassed TC to a 90mm non-IF lens. 20mm thick TC, 1:1 90mm lens; m = (90+90+20)/90 -1 = 1.2x, effective f-stop multiplier ~ 1.2x 20mm thick TC, 1:2 90mm lens; m = (90+45+20)/90 -1 = 0.72x, effective f-stop multiplier ~ 0.72x 30mm thick TC, 1:1 90mm lens; m = (90+90+30)/90 -1 = 1.33x, effective f-stop multiplier ~ 1.33x 30mm thick TC, 1:2 90mm lens; m = (90+45+30) /90- 1 = 0.83x, effective f-stop multiplier ~ 0.83x Adding a TC behind a lens does NOT change the working distance, and the factor increasing the magnification is the same as the factor increasing f-stop. That is, if a 2x TC is added behind a lens, working distance does not change but both magnification and f-stop are increased by 2x. I just tested to make sure this is the case. Last edited by newarts; 11-10-2011 at 05:19 PM.

11-10-2011, 05:44 PM	#38
Azzy Senior Member Join Date: Jan 2010 Photos: Albums Posts: 201 Original Poster	Yeah its the 90mm macro DI 1:1...so If I understood newarts correctly, to get 2:1 mag on the tamron I would need a 90mm thick ext tube / deglassed TC ? (90+90+90)/90-1 ? Last edited by Azzy; 11-10-2011 at 05:50 PM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Need cheap macro lens for K10D	K20D	Pentax SLR Lens Discussion	16	01-11-2011 08:44 PM
Cheap, Old Macro	soppy	Pentax SLR Lens Discussion	19	09-21-2010 04:36 PM
Sigma 28-80 Macro lens found CHEAP!	azcavalier	Pentax SLR Lens Discussion	12	11-13-2009 02:37 PM
What's a good, cheap macro lens?	joeyc	Pentax SLR Lens Discussion	38	08-24-2009 07:48 PM
Cheap DIY macro lens!	ftpaddict	Pentax SLR Lens Discussion	9	11-25-2008 01:00 AM

11-10-2011, 03:39 PM	#31
Azzy Senior Member Join Date: Jan 2010 Photos: Albums Posts: 201 Original Poster	I'm actually very close in obtaining Tamron 90mm for reasonable price from another member here. It beat the Lester dine kit that some members recommended as well due to the weight / no AF for other general usage. Quote: * For farther work and lotsa mag: Any affordable 90-100-105mm A-type or AF macro lens; 4-6 deglassed 2x TCs. Quote: #1: For a non-macro lens, yes. For a macro lens, the MFD doubles. A non-reversed lens cannot focus closer than its focal length. #2: Light is cut by 2 f-stops. So at 100/2.8 lens with MFD=10cm, with a 2x TC, becomes a 200/5.6mm lens with MFD=200mm. So Rico, even if I deglass the 2xTC I will cut 2 f-stops ? So the 90mm tammy would become 180mm F4 ? What kind of mag ratio I would obtain on the mfd ? and if the effect is multipled 6 2x TC would = 12:1 mag ? This deglassed TC option is highly desirable for me since I'll keep farther MFD from the subject

11-10-2011, 04:03 PM	#32
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by Azzy It beat the Lester dine kit that some members recommended It beat the who kit? Um, not sure where you got that info from - care to share? --

11-10-2011, 04:09 PM	#33
Azzy Senior Member Join Date: Jan 2010 Photos: Albums Posts: 201 Original Poster	Originally posted by RioRico A Lester Dine dental-macro lens with a built-in ringflash. Can't be beat! from what a gather its pretty much the vivitar 100m s1 macro lens which has quite a cult status in macro world...

11-10-2011, 04:16 PM	#34
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by Azzy from what a gather its pretty much the vivitar 100m s1 macro lens which has quite a cult status in macro world... The Vivitar S1 2.5 105mm <- Same lens as the 105 2.8 Lester Dine both manufactured by Kiron. The Tammy is a good choice, it is however not as good as the Kiron 105's optically (although you could PP to get better results), it does have the advantage of being AF which may come in handy if shooting other things besides macro. ..

11-10-2011, 05:07 PM	#36
RioRico Veteran Member Join Date: Jun 2008 Location: Limbo, California Posts: 11,263	Originally posted by newarts At 1:1 mag the working distance is 2X focal length - in this case, 200mm. Correction noted and applied. Thanks! Quote: Be aware that TC's are often only about 20mm thick so a de-glassed TC won't increase the magnification of a long focal length lens by much. All four of my PK 2x TCs measure thicker than that. An Albinar M-type and two 2 deglassed A-types (Focal and Promaster) measure 26mm; a Cambron M-type measures 31mm thick. No, these won't significantly boost magnification of longer glass. They are useful only with a limited subset of lenses. My A-type and AF collection is rather small. One TC on a 28mm lens demands a working distance only about 1in in front of the lens; too close. I can use one or both on the 35-70 and a 50mm. Using both on a 135mm doesn't put me into macro territory; ditto with zooms in the 70-210mm range except at the short end..

11-10-2011, 05:11 PM	#37
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by newarts Which Tamron 90 are we talking about? 1:1 or 1:2? My experience is with the 90mm SP Di 1:1 and guessing that is the one he is referencing... --

11-10-2011, 06:01 PM	#39
Laurentiu Cristofor Banned Join Date: Nov 2009 Location: WA Photos: Albums Posts: 3,055	Originally posted by joe.penn The Tammy is a good choice, it is however not as good as the Kiron 105's optically In what ways is the Tamron not as good as the Kiron optically? Any examples showing the difference would be much appreciated.

11-10-2011, 06:10 PM	#40
Azzy Senior Member Join Date: Jan 2010 Photos: Albums Posts: 201 Original Poster	Originally posted by newarts . At 1:1 mag the working distance is 2X focal length - in this case, 200mm. Be aware that TC's are often only about 20mm thick so a de-glassed TC won't increase the magnification of a long focal length lens by much. A standard 2X TC behind your Tamron zoom should give about 1:1 magnification. Finally, the working distance for a Raynox 150 on a 300mm lens focused at infinity (1.4x) isn't bad; about 214mm ~ 8.3" a little more than a 100mm macro lens at 1:1 I didn't know how I missed this post....I thought Raynox working distance is pretty close ~4" The tamron 90mm MFD is 3.9" or 99mm...so with the raynox it pretty much double the MFD for 1:1 mag!!!! Is there any reason (aside having AF portrait lens) picking the more expensive 90mm tamron over this combo ?

11-10-2011, 06:11 PM	#41
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Originally posted by Azzy Yeah its the 90mm macro DI 1:1...so If I understood newarts correctly, to get 2:1 mag on the tamron I would need a 90mm thick ext tube / deglassed TC ? (90+90+90)/90-1 ? Yes. A simpler way (although the image quality might not be as good) is to just use a 2X teleconverter.

11-10-2011, 06:29 PM	#42
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Originally posted by Azzy ... Is there any reason (aside having AF portrait lens) picking the more expensive 90mm tamron over this combo ? Well, the 90mm Tamron might be a little better IQ up to 1:1, but looking at the results people get with the Raynox on a good zoom, the 90mm Tamron cannot be a whole lot better. If the photos will be displayed electronically then I'll bet that any differences will be hard to see. One drawback of the Raynox route is the edges of the photo won't be as sharp as the center. This makes no practical difference with natural subjects. It might help you to spend a few minutes looking at the long Raynox Macro Club thread to see what quality to expect: https://www.pentaxforums.com/forums/lens-clubs/74221-raynox-macro-club.html If you'd like better quality put an el-nikkor 50:2.8 on a bellows for less than $100. Use a glass-less PK/A TC to trick the camera into thinking the bellows is an A type lens. There are other tricks available to fool the camera so the automatic flash will work with an inexpensive bellows.

11-10-2011, 07:00 PM	#43
excanonfd Veteran Member Join Date: Jan 2010 Location: Vancouver, BC Posts: 1,421	Originally posted by Laurentiu Cristofor In what ways is the Tamron not as good as the Kiron optically? Any examples showing the difference would be much appreciated. Yup, I am interested too. Please put up some lens resolution test results (no pixie dust or pixie dungs, please!). Meanwhile, I did find this little snippet from this article: Pentax Lens Review by Peter Spiro Some recent advertisements from Carl Zeiss claim that the Zeiss Planar T 60mm macro lens can resolve 150 lines per mm. Perhaps one should expect no less from a lens that sells at a discount mail order dealer for about US$800. If true, this would give it a higher resolution than any lens ever tested in Modern Photography. The peak I found there was 110 for a 90mm macro by Tamron. Of course, this is the best resolution at the best f/stop for the lens. Please read the last two sentences from the above paragraph...

11-11-2011, 12:29 AM	#44
Laurentiu Cristofor Banned Join Date: Nov 2009 Location: WA Photos: Albums Posts: 3,055	Originally posted by excanonfd The peak I found there was 110 for a 90mm macro by Tamron. Was that the adaptall version? Someone had posted old reviews (from Modern Photography maybe?) comparing macro lenses and the 52B came out much better than the VS1 and pretty much anything else. Can't find that post now though.

11-11-2011, 01:01 AM	#45
hoanpham Veteran Member Join Date: Nov 2009 Location: Strand Photos: Gallery \| Albums Posts: 1,366	Originally posted by excanonfd Originally posted by Laurentiu Cristofor Quote In what ways is the Tamron not as good as the Kiron optically? Any examples showing the difference would be much appreciated. Yup, I am interested too I have the Tamron 90/2.5 adaptall2 with belonging TCx2, new Tamron90/2.8 AF, new Sigma105/2.8 AF, fujinon55 w belonging tube, pentax M50/4 + tube + pentax TCx2 + pentax TCx1.4, bellow, multiple sets of tubes, tried reverse ring on many of primes - but no Kiron. I havent try stacking primes, like 20/28/30/50 on 135/150/200. I though modern optics with AF on the Tamron90/2.8 and the Sigma 105/2.8 should be at least equal the Kiron if not better due to newer coating and such?