75-150mm M question

LensBeginner · 01-07-2015, 01:49 PM

Hi all,
I'm still in my quest for a telephoto zoom, and have started considering the "stack of primes" as well...
Please don't tell me I've got my priorities mixed up "only" because I've been looking at the 55-300 WR, 70-200 2.8 and now this (

): I need the focal lengths and the versatility, everything else is not so important to me (I could even live with noting down the focal lengths by hand in addition to the apertures - I believe this will be the case with this lens...).

One question comes to mind... since what I'm looking for in a tele zoom is mainly the long end, how close is this to a "true" 150mm?
I mean, I remember reading somewhere than there's a little bit of "cheating" involved in zooms, esp. not at infinity, so that the long end is not all that long after all.
Can anyone comment on this? my current "go-to" tele zoom is a Shitgma UC 70-210mm f/4-5.6 (and it's falling apart...)

Rimfiredude · 01-07-2015, 02:33 PM - **1 Like**

I have owned zoom after zoom after zoom. When I finally found my precious 35-105A, it rarely came off the camera. It is my everyday walk around lens. I even used it for Xmas with the family. It may not be for your situation, but it usually is wide enough, long enough and fast enough and sharp enough for just about every situation for me.

jimr-pdx · 01-07-2015, 03:01 PM - **1 Like**

I had a Rikenon XR 70-150 and it was a fine lens, wish I had kept it as it's mighty rare on the market. I'd think the M 75-150 would do similar good work though.

Maybe the SMC 45-125mm f/4 would be more suitable, less overlap with your other ideas. It doesn't get the ratings of the 75-150 but read the review texts and see why the ratings are what they are; some times reviewers are tough, others may dislike features that are ideal for you!

LensBeginner · 01-07-2015, 03:10 PM

Originally posted by jimr-pdx

I had a Rikenon XR 70-150 and it was a fine lens, wish I had kept it as it's mighty rare on the market. I'd think the M 75-150 would do similar good work though.

Maybe the SMC 45-125mm f/4 would be more suitable, less overlap with your other ideas. It doesn't get the ratings of the 75-150 but read the review texts and see why the ratings are what they are; some times reviewers are tough, others may dislike features that are ideal for you!

Nope, I don't have an overlap issue, it's meant to be an alternative purchase!
The 80-200m M seems to be more suitable as far as focal range is concerned, but 1) I don't like some pictures in the review pages (on this site) much (maybe it's just me, maybe it's the photos and not the lens), 2) much more purple fringing, and I hate that and finally 3) a wee bit slower (f/4 vs f/4.5).
How do they compare to each other (M 75-150 4 vs M 80-200 4.5)?

**kiwi_jono** · 01-07-2015, 03:16 PM - **1 Like**

Hi I have the M 75 - 150 f4 amongst other lenses. Its a great lens for sure.
I have not tried to measure focal length or test for change of focal length at close versus infinity focus but I can say that focal length compares well to other lenses I have. I have not seen obvious focal length changes when changing focus.
https://www.flickr.com/photos/kiwi_jono/16003436258/

That all said I have a new Tamron 70-200 f2.8 or order which is should be a significant step up.

**dunerunner** · 01-07-2015, 03:25 PM - **1 Like**

I have had a 75-150 for about 4 years now and agree with Kiwi's post above. With the price you will probably pay for an M 75-150, it might be worth getting one and trying it out for your self if you can.

**dms** · 01-07-2015, 03:28 PM - **1 Like**

"Cheating" is generally not the case. In order to design a lens (zoom or not) that does not alter in physical length as one focuses, apparently other constraints come into play, and generally the FL decreases as one close focuses. Although I neither have such a lens, or have looked into it further, I believe It will not be important until one approaches the macro range (as a guess magnification about 0.1 and larger).

LensBeginner · 01-07-2015, 03:53 PM

Originally posted by dms

"Cheating" is generally not the case. In order to design a lens (zoom or not) that does not alter in physical length as one focuses, apparently other constraints come into play, and generally the FL decreases as one close focuses. Although I neither have such a lens, or have looked into it further, I believe It will not be important until one approaches the macro range (as a guess magnification about 0.1 and larger).

That's why it was in inverted commas... that, and the fact that I didn't remember exactly what it was about, and also being told once that internal focusing & other mystiques were "something you don't want to talk about"...

Needing reach mainly to cover (duh!) a distance would mean that it will be probably be negligible 90% of the time, I believe...

jonby · 01-07-2015, 07:01 PM - **2 Likes**

I haven't tried to measure the focal length range of the 75-150 as such, but I have compared it at the extremes to prime lenses of 80mm and 135mm. Assuming the stated focal lengths of these lenses are accurate, then I'd definitely say that the stated 75-150 range is optimistic. I'd guess that the true range is around 78 to 140mm. Most zooms short change you a bit in this respect but I would say that the 75-150 is worse than most. Fortunately it makes up for this in other respects - very nice image quality, excellent construction and it's very small. I also have the 70-210 A, which might suit your needs better if you really want the longer focal lengths, but I personally prefer the 75-150 in most cases. My observations about the two are as follows:

The 75-150 is notably sharper at f4 across the frame and throughout the range.
At f5.6 there's not much difference but I'd still give it to the 75-150.
The 75-150 has somewhat nicer construction. The 70-210 has a tendency to develop a small amount of play in the zoom/focus ring.
The 75-150 is less prone to zoom creep.
The 75-150 has nicer manual focus properties - once you have set focus it is less likely to move accidentally. Also the focus throw of the 70-210 is a little short at the long end of the zoom, making it a little twitchy, while the 75-150 remains easy to control.
The 70-210 is an A series and so records the aperture, which is useful.
The 70-210 is a lot bigger and heavier.

Of course, some of these observations are only true of my copies of the lenses. I recommend either of these lenses.

Sorry but I haven't used the other lenses you mention. Examples I have seen from the DA 55-300 suggest it follows the pattern of most consumer DA zooms - ie that centre sharpness is generally good but edge sharpness is flakey.

01-07-2015, 01:49 PM	#1
LensBeginner Veteran Member Join Date: Sep 2014 Photos: Albums Posts: 4,696	75-150mm M question Hi all, I'm still in my quest for a telephoto zoom, and have started considering the "stack of primes" as well... Please don't tell me I've got my priorities mixed up "only" because I've been looking at the 55-300 WR, 70-200 2.8 and now this ( ): I need the focal lengths and the versatility, everything else is not so important to me (I could even live with noting down the focal lengths by hand in addition to the apertures - I believe this will be the case with this lens...). One question comes to mind... since what I'm looking for in a tele zoom is mainly the long end, how close is this to a "true" 150mm? I mean, I remember reading somewhere than there's a little bit of "cheating" involved in zooms, esp. not at infinity, so that the long end is not all that long after all. Can anyone comment on this? my current "go-to" tele zoom is a Shitgma UC 70-210mm f/4-5.6 (and it's falling apart...)

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01-07-2015, 02:33 PM - 1 Like	#2
Rimfiredude Veteran Member Join Date: Oct 2014 Location: Washington Photos: Gallery Posts: 2,176	I have owned zoom after zoom after zoom. When I finally found my precious 35-105A, it rarely came off the camera. It is my everyday walk around lens. I even used it for Xmas with the family. It may not be for your situation, but it usually is wide enough, long enough and fast enough and sharp enough for just about every situation for me.

01-07-2015, 03:01 PM - 1 Like	#3
jimr-pdx Pentaxian Join Date: May 2010 Location: now 1 hour north of PDX Photos: Gallery \| Albums Posts: 3,897	I had a Rikenon XR 70-150 and it was a fine lens, wish I had kept it as it's mighty rare on the market. I'd think the M 75-150 would do similar good work though. Maybe the SMC 45-125mm f/4 would be more suitable, less overlap with your other ideas. It doesn't get the ratings of the 75-150 but read the review texts and see why the ratings are what they are; some times reviewers are tough, others may dislike features that are ideal for you!

01-07-2015, 03:10 PM	#4
LensBeginner Veteran Member Join Date: Sep 2014 Photos: Albums Posts: 4,696 Original Poster	Originally posted by jimr-pdx I had a Rikenon XR 70-150 and it was a fine lens, wish I had kept it as it's mighty rare on the market. I'd think the M 75-150 would do similar good work though. Maybe the SMC 45-125mm f/4 would be more suitable, less overlap with your other ideas. It doesn't get the ratings of the 75-150 but read the review texts and see why the ratings are what they are; some times reviewers are tough, others may dislike features that are ideal for you! Nope, I don't have an overlap issue, it's meant to be an alternative purchase! The 80-200m M seems to be more suitable as far as focal range is concerned, but 1) I don't like some pictures in the review pages (on this site) much (maybe it's just me, maybe it's the photos and not the lens), 2) much more purple fringing, and I hate that and finally 3) a wee bit slower (f/4 vs f/4.5). How do they compare to each other (M 75-150 4 vs M 80-200 4.5)?

01-07-2015, 03:16 PM - 1 Like	#5
kiwi_jono Loyal Site Supporter Join Date: Dec 2009 Location: Christchurch, New Zealand Photos: Gallery \| Albums Posts: 2,437	Hi I have the M 75 - 150 f4 amongst other lenses. Its a great lens for sure. I have not tried to measure focal length or test for change of focal length at close versus infinity focus but I can say that focal length compares well to other lenses I have. I have not seen obvious focal length changes when changing focus. https://www.flickr.com/photos/kiwi_jono/16003436258/ That all said I have a new Tamron 70-200 f2.8 or order which is should be a significant step up.

01-07-2015, 03:25 PM - 1 Like	#6
dunerunner Site Supporter Join Date: Jan 2010 Location: The Black Hills Photos: Gallery \| Albums Posts: 1,108	I have had a 75-150 for about 4 years now and agree with Kiwi's post above. With the price you will probably pay for an M 75-150, it might be worth getting one and trying it out for your self if you can.

01-07-2015, 03:28 PM - 1 Like	#7
dms Site Supporter Join Date: Aug 2011 Location: New York, NY Photos: Gallery Posts: 2,192	"Cheating" is generally not the case. In order to design a lens (zoom or not) that does not alter in physical length as one focuses, apparently other constraints come into play, and generally the FL decreases as one close focuses. Although I neither have such a lens, or have looked into it further, I believe It will not be important until one approaches the macro range (as a guess magnification about 0.1 and larger).

01-07-2015, 03:53 PM	#8
LensBeginner Veteran Member Join Date: Sep 2014 Photos: Albums Posts: 4,696 Original Poster	Originally posted by dms "Cheating" is generally not the case. In order to design a lens (zoom or not) that does not alter in physical length as one focuses, apparently other constraints come into play, and generally the FL decreases as one close focuses. Although I neither have such a lens, or have looked into it further, I believe It will not be important until one approaches the macro range (as a guess magnification about 0.1 and larger). That's why it was in inverted commas... that, and the fact that I didn't remember exactly what it was about, and also being told once that internal focusing & other mystiques were "something you don't want to talk about"... Needing reach mainly to cover (duh!) a distance would mean that it will be probably be negligible 90% of the time, I believe...

01-07-2015, 07:01 PM - 2 Likes	#9
jonby Senior Member Join Date: Nov 2013 Posts: 161	I haven't tried to measure the focal length range of the 75-150 as such, but I have compared it at the extremes to prime lenses of 80mm and 135mm. Assuming the stated focal lengths of these lenses are accurate, then I'd definitely say that the stated 75-150 range is optimistic. I'd guess that the true range is around 78 to 140mm. Most zooms short change you a bit in this respect but I would say that the 75-150 is worse than most. Fortunately it makes up for this in other respects - very nice image quality, excellent construction and it's very small. I also have the 70-210 A, which might suit your needs better if you really want the longer focal lengths, but I personally prefer the 75-150 in most cases. My observations about the two are as follows: The 75-150 is notably sharper at f4 across the frame and throughout the range. At f5.6 there's not much difference but I'd still give it to the 75-150. The 75-150 has somewhat nicer construction. The 70-210 has a tendency to develop a small amount of play in the zoom/focus ring. The 75-150 is less prone to zoom creep. The 75-150 has nicer manual focus properties - once you have set focus it is less likely to move accidentally. Also the focus throw of the 70-210 is a little short at the long end of the zoom, making it a little twitchy, while the 75-150 remains easy to control. The 70-210 is an A series and so records the aperture, which is useful. The 70-210 is a lot bigger and heavier. Of course, some of these observations are only true of my copies of the lenses. I recommend either of these lenses. Sorry but I haven't used the other lenses you mention. Examples I have seen from the DA 55-300 suggest it follows the pattern of most consumer DA zooms - ie that centre sharpness is generally good but edge sharpness is flakey.