apochromats for K-mount

Class A · 04-04-2011, 05:06 AM

Originally posted by rparmar

Most lens manufactures use the designation "APO" to indicate an apochromat; Tamron uses "LD".

That's not true. Tamron's "LD" only signals that "one or more very low dispersion elements" have been used. It is not claiming the whole optical design to be an APO design.

It doesn't make sense to include Tamron lenses with an "LD" designation in a list of APO lenses.

**Digitalis** · 04-04-2011, 05:41 AM

Originally posted by Class A

It doesn't make sense to include Tamron lenses with an "LD" designation in a list of APO lenses

No, it doesn't especially considering many of them are zoom lenses with focal length ranges going well under 50mm. As I have said before there aren't any true Apochromatic 35mm lenses made with focal lengths under 100mm.

And for the record: the Schneider Apo-Digitar, Rodenstock HR Digaron-S are not 35mm lenses, they are designed for large format view cameras equipped with digital medium format backs.

**rparmar** · 04-04-2011, 05:50 AM

Thank you -- I was misinformed by an article I read. After viewing some images and test results I agree these cannot be included.

**Digitalis** · 04-04-2011, 06:05 AM

you also might want to add the Pentax FA*300mm f/2.8 and pentax FA*600mm f/4 - These two lenses I have used in the past and their performance fits well within the definition of an apochromatic lens. Although the literature describing those two lenses does not explicitly designate them as such, but a close look at their lens design schematics strongly suggest this is the case*.

the funny thing I have observed is that all the major 35mm camera manufacturers E.g Canon,Nikon and Pentax do not really mention of apochromatic lens designs in their lens line ups, but Sigma,Tamron and Tamron do.

*although I have never used the pentax FA*250-600mm f/5.6 from looking at the lens design the first three elements are in a classic apochromatic arrangement, so I would tentatively put that lens on the list as well. There may be others on this forum who own this lens that could provide an account of whether my observation is correct or not.

Last edited by Digitalis; 04-04-2011 at 06:16 AM.

stanislav · 04-04-2011, 06:26 AM

Sigma 70-200mm f2.8 APO EX (non macro pre-DG version)

Sigma 70-300mm f4-5.6 APO Macro Super (pre-DG version, this should be improved 70-300 APO macro, hence the "Super" label)

Sigma 50-500mm f4-6.3 APO EX (Bigma)

Abbazz · 04-04-2011, 08:12 AM

Apart from the 3 Voigtländer Apo-Lanthar and a few Sigma lenses (which are more achromatic than truly apochromatic lenses), there are no other apochromatic lenses in Pentax K mount.

There are of course the Quartz Takumar and Ultra Achromatic Takumar lenses, but these are rare as hens' teeth and they are not K mount but M42 lenses. A few APO lenses were also made in M42 mount by lensmakers from former USSR countries, like the APO-Telezenitar 135/2.8 or the APO-Telezenitar 300/4.5 from Krasnogorsky Zavod.

If you are willing to use adapters or do mount convertion, there's the amazingly good but incredibly expensive CoastalOptics UV-VIS-IR 60mm Apo Macro (Nikon mount), as well as a few Leica Apo lenses (Leica 90/2 APO Summicron-R, 180/2.8 APO-Elmarit-R, 280/4 APO-Telyt-R, or 300/4 APO) that are of very high quality indeed.

And, last but not least, don't forget that many mirror lenses are naturally apochromatic or near apochromatic...

Cheers!

Abbazz

elho_cid · 04-04-2011, 08:49 AM

Perhaps some lenses are apochromatic without having APO in their names? I can only judge by experince but from what I have seen many Pentax lenses do have less problems with fringing than Sigma lenses bearing APO label. I recall DA*50-135, DFA50, DA*300, FA135 and perhaps others.
Please enlighten me.

macTak · 04-10-2011, 08:58 AM

While not exactly K-mount, there are some enlarging lenses that are true APO designs

aliasant · 04-10-2011, 09:13 AM

I have a nice Sigma 50-200 Apo 3.5-4.5 PK/A mount

Nick Siebers · 04-10-2011, 02:08 PM

Originally posted by Abbazz

Apart from the 3 Voigtländer Apo-Lanthar and a few Sigma lenses (which are more achromatic than truly apochromatic lenses), there are no other apochromatic lenses in Pentax K mount.

Cheers!

Abbazz

I know you know a lot about this, but I definitely have a lens claiming to be apochromatic in the Rikenon XR 300mm f/4.5 prime. So... there is one other, and may even be one or two more, right?

**nater** · 04-10-2011, 02:30 PM

Tokina labelled a number of their zoom lenses as APO, such as the Tokina 80-200mm f2.8 AT-X 828 AF Pro SD and Tokina 80-400mm f4.5-5.6 AT-X 840 AF SD.

Class A · 04-10-2011, 03:38 PM

Originally posted by aliasant

I have a nice Sigma 50-200 Apo 3.5-4.5 PK/A mount

I'd be very surprised if there were a lot of merit to this "APO" designation. Seems like it has been used liberally similarly to how the "MACRO" designation is often used for lenses which just have some close focusing ability (but are nowhere near true macros).

macTak · 04-10-2011, 04:38 PM

Originally posted by Class A

I'd be very surprised if there were a lot of merit to this "APO" designation. Seems like it has been used liberally similarly to how the "MACRO" designation is often used for lenses which just have some close focusing ability (but are nowhere near true macros).

Agreed. I think most of the APO labelings of lenses should not be taken at face value. Of course, it really depends on how you define it--I mean some of these lenses might be APO at one focal lengh/aperature setting/focal distance, but not throughout most of the options. The APO-Lanthars really seem the best from what I've seens as far as actually being APO consistantly. I'm sure the APO enlarging lenses are really APO as well, although I don't know what the correction would be like outside of their standard focus range (actually, I've just won an APO-Rodagon for a song and am looking forward to giving it a try).

Blue · 04-10-2011, 07:04 PM

Originally posted by Digitalis

you also might want to add the Pentax FA*300mm f/2.8 and pentax FA*600mm f/4 - These two lenses I have used in the past and their performance fits well within the definition of an apochromatic lens. Although the literature describing those two lenses does not explicitly designate them as such, but a close look at their lens design schematics strongly suggest this is the case*.

the funny thing I have observed is that all the major 35mm camera manufacturers E.g Canon,Nikon and Pentax do not really mention of apochromatic lens designs in their lens line ups, but Sigma,Tamron and Tamron do.

*although I have never used the pentax FA*250-600mm f/5.6 from looking at the lens design the first three elements are in a classic apochromatic arrangement, so I would tentatively put that lens on the list as well. There may be others on this forum who own this lens that could provide an account of whether my observation is correct or not.

Marc Langille has all of these.

aliasant · 04-11-2011, 01:32 AM

Originally posted by Class A

I'd be very surprised if there were a lot of merit to this "APO" designation. Seems like it has been used liberally similarly to how the "MACRO" designation is often used for lenses which just have some close focusing ability (but are nowhere near true macros).

You are probably right. I have no knowledge about this but I did test this lens against my Viv S1 70-210 Komine version at 150mm.
The Viv had some CA but the sigma had none what so ever and also slightly better contrast and colors.
Now I dont know which one to keep. Trying to cut down on the amount of lenses but I probably have to keep em both since they have different strengths.

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04-04-2011, 05:06 AM	#16
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by rparmar Most lens manufactures use the designation "APO" to indicate an apochromat; Tamron uses "LD". That's not true. Tamron's "LD" only signals that "one or more very low dispersion elements" have been used. It is not claiming the whole optical design to be an APO design. It doesn't make sense to include Tamron lenses with an "LD" designation in a list of APO lenses.

04-04-2011, 05:41 AM	#17
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	Originally posted by Class A It doesn't make sense to include Tamron lenses with an "LD" designation in a list of APO lenses No, it doesn't especially considering many of them are zoom lenses with focal length ranges going well under 50mm. As I have said before there aren't any true Apochromatic 35mm lenses made with focal lengths under 100mm. And for the record: the Schneider Apo-Digitar, Rodenstock HR Digaron-S are not 35mm lenses, they are designed for large format view cameras equipped with digital medium format backs.

04-04-2011, 05:50 AM	#18
rparmar Site Supporter Join Date: Jan 2008 Photos: Gallery Posts: 8,819 Original Poster	Thank you -- I was misinformed by an article I read. After viewing some images and test results I agree these cannot be included.

04-04-2011, 06:05 AM	#19
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	you also might want to add the Pentax FA300mm f/2.8 and pentax FA600mm f/4 - These two lenses I have used in the past and their performance fits well within the definition of an apochromatic lens. Although the literature describing those two lenses does not explicitly designate them as such, but a close look at their lens design schematics strongly suggest this is the case. the funny thing I have observed is that all the major 35mm camera manufacturers E.g Canon,Nikon and Pentax do not really mention of apochromatic lens designs in their lens line ups, but Sigma,Tamron and Tamron do. although I have never used the pentax FA250-600mm f/5.6 from looking at the lens design the first three elements are in a classic apochromatic arrangement, so I would tentatively put that lens on the list as well. There may be others on this forum who own this lens that could provide an account of whether my observation is correct or not. Last edited by Digitalis; 04-04-2011 at 06:16 AM.*

04-04-2011, 06:26 AM	#20
stanislav Senior Member Join Date: Jan 2010 Location: Stockholm Photos: Albums Posts: 125	Sigma 70-200mm f2.8 APO EX (non macro pre-DG version) Sigma 70-300mm f4-5.6 APO Macro Super (pre-DG version, this should be improved 70-300 APO macro, hence the "Super" label) Sigma 50-500mm f4-6.3 APO EX (Bigma)

04-04-2011, 08:12 AM	#21
Abbazz Pentaxian Join Date: Nov 2006 Location: Jakarta Posts: 667	Apart from the 3 Voigtländer Apo-Lanthar and a few Sigma lenses (which are more achromatic than truly apochromatic lenses), there are no other apochromatic lenses in Pentax K mount. There are of course the Quartz Takumar and Ultra Achromatic Takumar lenses, but these are rare as hens' teeth and they are not K mount but M42 lenses. A few APO lenses were also made in M42 mount by lensmakers from former USSR countries, like the APO-Telezenitar 135/2.8 or the APO-Telezenitar 300/4.5 from Krasnogorsky Zavod. If you are willing to use adapters or do mount convertion, there's the amazingly good but incredibly expensive CoastalOptics UV-VIS-IR 60mm Apo Macro (Nikon mount), as well as a few Leica Apo lenses (Leica 90/2 APO Summicron-R, 180/2.8 APO-Elmarit-R, 280/4 APO-Telyt-R, or 300/4 APO) that are of very high quality indeed. And, last but not least, don't forget that many mirror lenses are naturally apochromatic or near apochromatic... Cheers! Abbazz

04-04-2011, 08:49 AM	#22
elho_cid Veteran Member Join Date: Dec 2007 Location: Prague Photos: Gallery Posts: 1,199	Perhaps some lenses are apochromatic without having APO in their names? I can only judge by experince but from what I have seen many Pentax lenses do have less problems with fringing than Sigma lenses bearing APO label. I recall DA50-135, DFA50, DA300, FA135 and perhaps others. Please enlighten me.

04-10-2011, 08:58 AM	#23
macTak Veteran Member Join Date: Apr 2010 Photos: Gallery Posts: 759	While not exactly K-mount, there are some enlarging lenses that are true APO designs

04-10-2011, 09:13 AM	#24
aliasant Veteran Member Join Date: Feb 2010 Location: Stockholm Photos: Gallery \| Albums Posts: 634	I have a nice Sigma 50-200 Apo 3.5-4.5 PK/A mount

04-10-2011, 02:08 PM	#25
Nick Siebers Veteran Member Join Date: Jun 2008 Location: Madison, WI Photos: Gallery \| Albums Posts: 2,165	Originally posted by Abbazz Apart from the 3 Voigtländer Apo-Lanthar and a few Sigma lenses (which are more achromatic than truly apochromatic lenses), there are no other apochromatic lenses in Pentax K mount. Cheers! Abbazz I know you know a lot about this, but I definitely have a lens claiming to be apochromatic in the Rikenon XR 300mm f/4.5 prime. So... there is one other, and may even be one or two more, right?

04-10-2011, 02:30 PM	#26
nater Loyal Site Supporter Join Date: Aug 2009 Location: New England Photos: Albums Posts: 706	Tokina labelled a number of their zoom lenses as APO, such as the Tokina 80-200mm f2.8 AT-X 828 AF Pro SD and Tokina 80-400mm f4.5-5.6 AT-X 840 AF SD.

04-10-2011, 03:38 PM	#27
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by aliasant I have a nice Sigma 50-200 Apo 3.5-4.5 PK/A mount I'd be very surprised if there were a lot of merit to this "APO" designation. Seems like it has been used liberally similarly to how the "MACRO" designation is often used for lenses which just have some close focusing ability (but are nowhere near true macros).

04-10-2011, 04:38 PM	#28
macTak Veteran Member Join Date: Apr 2010 Photos: Gallery Posts: 759	Originally posted by Class A I'd be very surprised if there were a lot of merit to this "APO" designation. Seems like it has been used liberally similarly to how the "MACRO" designation is often used for lenses which just have some close focusing ability (but are nowhere near true macros). Agreed. I think most of the APO labelings of lenses should not be taken at face value. Of course, it really depends on how you define it--I mean some of these lenses might be APO at one focal lengh/aperature setting/focal distance, but not throughout most of the options. The APO-Lanthars really seem the best from what I've seens as far as actually being APO consistantly. I'm sure the APO enlarging lenses are really APO as well, although I don't know what the correction would be like outside of their standard focus range (actually, I've just won an APO-Rodagon for a song and am looking forward to giving it a try).

04-10-2011, 07:04 PM	#29
Blue Moderator Site Supporter Join Date: Jun 2008 Location: Florida Hill Country Photos: Gallery \| Albums Posts: 17,377	Originally posted by Digitalis you also might want to add the Pentax FA300mm f/2.8 and pentax FA600mm f/4 - These two lenses I have used in the past and their performance fits well within the definition of an apochromatic lens. Although the literature describing those two lenses does not explicitly designate them as such, but a close look at their lens design schematics strongly suggest this is the case. the funny thing I have observed is that all the major 35mm camera manufacturers E.g Canon,Nikon and Pentax do not really mention of apochromatic lens designs in their lens line ups, but Sigma,Tamron and Tamron do. although I have never used the pentax FA*250-600mm f/5.6 from looking at the lens design the first three elements are in a classic apochromatic arrangement, so I would tentatively put that lens on the list as well. There may be others on this forum who own this lens that could provide an account of whether my observation is correct or not. Marc Langille has all of these.

04-11-2011, 01:32 AM	#30
aliasant Veteran Member Join Date: Feb 2010 Location: Stockholm Photos: Gallery \| Albums Posts: 634	Originally posted by Class A I'd be very surprised if there were a lot of merit to this "APO" designation. Seems like it has been used liberally similarly to how the "MACRO" designation is often used for lenses which just have some close focusing ability (but are nowhere near true macros). You are probably right. I have no knowledge about this but I did test this lens against my Viv S1 70-210 Komine version at 150mm. The Viv had some CA but the sigma had none what so ever and also slightly better contrast and colors. Now I dont know which one to keep. Trying to cut down on the amount of lenses but I probably have to keep em both since they have different strengths.