[rob_k20d]

Hi,

I am a little confused about the M prime lenses. I understand that these lenses should be pretty top quality.

However, I bought an M 28mm 2.8, and was disappointed, particularly by the lack of contrast. It seemed to be in excellent condition (pretty much looked like new) but as I say, it just seemed to lack contrast, and was disappointing.

I also bought an M 100mm macro f4 and had the same experience - though in this case the lens wasn't in good condition, and had clouding in the lens. Obviously I would have just put it down to that, but because of my experience with the 28mm as well, I wondered if the old M lenses do just have less contrast than modern lenses, or something like that.

Just wondering if anyone has any thoughts on this.

[timo]

Hi,

I am a little confused about the M prime lenses. I understand that these lenses should be pretty top quality.

However, I bought an M 28mm 2.8, and was disappointed, particularly by the lack of contrast. It seemed to be in excellent condition (pretty much looked like new) but as I say, it just seemed to lack contrast, and was disappointing.

I also bought an M 100mm macro f4 and had the same experience - though in this case the lens wasn't in good condition, and had clouding in the lens. Obviously I would have just put it down to that, but because of my experience with the 28mm as well, I wondered if the old M lenses do just have less contrast than modern lenses, or something like that.

Just wondering if anyone has any thoughts on this.

Stopped down a bit all mine are contrasty enough (28/3.5, 50/1.4, 50/1.7, 100/2.8, 200/4). Fully wide the 28 loses a bit of detail contrast at the extreme edges, the 50s lose some contrast all over, the 100 is remarkably good at all apertures, and the 200 is pretty good wide open but at its best tighter than 5.6.

The M28/3.5 stopped down to f/8-11 is a great landscape lens.

What aperture were you working at? My K105 2.8 loses contrast terribly at f/2.8 (albeit producing a sort of romantic veil), but at f/4 something miraculous happens and it sorts itself out.

Even when these lenses are not at their best, a dab of sharpening in PP works wonders, and they're all fully usable wide open.

[jsherman999]

Hi,

I am a little confused about the M prime lenses. I understand that these lenses should be pretty top quality.

However, I bought an M 28mm 2.8, and was disappointed, particularly by the lack of contrast. It seemed to be in excellent condition (pretty much looked like new) but as I say, it just seemed to lack contrast, and was disappointing.

I also bought an M 100mm macro f4 and had the same experience - though in this case the lens wasn't in good condition, and had clouding in the lens. Obviously I would have just put it down to that, but because of my experience with the 28mm as well, I wondered if the old M lenses do just have less contrast than modern lenses, or something like that.

Just wondering if anyone has any thoughts on this.

.



Actually I find that the M 28 f/2.8 is a very contrasty lens for an older design - I wonder if you may have had a bad copy, or one with element separation or cleaning marks?

Here are some M 28 2.8 examples fropm my old copy:

.

[stevebrot]

I will echo Jay...Are you sure there is not an issue with your lens? Haze and/or fungus perhaps? Contrast with the M series Pentax primes is usually not an issue.


Steve

[Jewelltrail]

My copy of the M 28, 2.8 had plenty of contrast, @ all apertures.

[harmonica2]

I love the contrast of my copy as well. It is truly under-rated.

[m42man]

In my experience, very few vintage lenses can match the contrast and colours you expect from a modern Pentax lens, and the M series is no exception.

I wouldn't worry too much though, because most of these lenses are very sharp (if you focus them accurately!), and the contrast and colours can easily be adjusted in PP.

[jolepp]

I understand that using a hood would be especially adviseable with these to avoid flare or at least improve contrast.

[freewheeler]

A hood is important indeed.
For my m28/3.5 I use a Pentax 50mm hood,
which is sufficiënt for 28 on crop-sensor use.

[rob_k20d]

Thanks for the responses.

As I say, I am not at all convinced that it wasn't a problem with my particular lenses. One, however, did appear to be in excellent condition (but I am no expert).

I'm afraid I don't have either anymore (returned the one that was clearly damaged and sold the other).

Maybe it was just a bad copy, or maybe M42man is right and modern lenses will have more contrast (but it just needed a bit of a tweak).

Either way, thanks for all the responses.

[paperbag846]

However, I bought an M 28mm 2.8, and was disappointed, particularly by the lack of contrast. It seemed to be in excellent condition (pretty much looked like new) but as I say, it just seemed to lack contrast, and was disappointing.

This is a flare problem.

When I first bought my 28mm I was very dissapointed because I was used to my kit lens which is actually pretty good with flare, and came with a hood to boot.

Buy yourself a rubber hood designed for 50mm lenses. The 28mm's flare badly but in the right light they have plenty of contrast.

The one thing you might notice is a lack of colour saturation. Compared to the average pentax prime, the 28's are pretty realistic. The saturation will be less than some of your other lenses, but the contrast should be on par.

[stevebrot]

maybe M42man is right and modern lenses will have more contrast

I wondered about his assertion. I have a fair amount of vintage glass and have shot most of my photographic "life" with such being fairly vintage myself. I don't know that I can make a clear distinction between old and new regarding contrast. Perhaps it is because I don't have enough modern lenses to compare to? For example, my K 55/1.8 and M 50/1.8 both have as much snap as my FA 77 Limited. Ditto for my Russian Helios 44M whose design roots reach back to pre-WWII Germany. I shot some this last summer with a Super-Tak 28/3.5 that is every bit the equal to my FA 35/2.

As for flare resistance, there have been improvements to the SMC coatings since the mid-1970s, but the second generation coatings found in the early K-mount lenses are quite capable of quenching flare. That being said, I concur that almost all lenses benefit from using a hood. I find this particularly true with the digital sensor.


Steve

[paperbag846]

Steve, I find the DA series have the most contrast of any lens line I have tried on Pentax. It's a starkly modern look compared to any of the film lenses, including the FA series.

Some really nice vintage film lenses (K55 1.8, e.g.) might be better lenses overall, but the kit lens has more contrast. I always assumed it was a coatings thing, but I have no idea really.

[m42man]

Steve, I find the DA series have the most contrast of any lens line I have tried on Pentax. It's a starkly modern look compared to any of the film lenses, including the FA series.

Some really nice vintage film lenses (K55 1.8, e.g.) might be better lenses overall, but the kit lens has more contrast. I always assumed it was a coatings thing, but I have no idea really.

I should think the coatings would be the most likely explanation, and I think it's more a case of when the lens was made, rather than a DA/FA thing: I've got a late copy of the lowly FAJ 75-300, and it really does show up my vintage lenses regarding contrast/colour (actually, it's quite sharp too, so I must have been lucky!).

If I could figure out how to post an image, I would be able to show you what I mean...

[rob_k20d]

I don't think it was a flare issue - many of the photos were indoors.

Regarding the distinction between contrast and saturation, it is possible that I wasn't being discerning enough, and may have been a saturation issue, rather than contrast. I guess it just looked kind of dull, lacking something - but perfectly possible I mis-diagnosed what was lacking.

Regarding DA lenses versus other lenses, I have an FA 50 1.4 and an F 35-70 3.5-4.5, and have also had 2 old helios M42 lenses, and I think it was only the M lenses I have had an issue with.

Maybe I did just get unlucky.