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Forum: Pentax SLR Lens Discussion 11-08-2023, 03:32 PM  
Super Takumar 85mm f/1.9 - Not sharp at all
Posted By whojammyflip
Replies: 21
Views: 1,607
I have the Pentax M 85mm (as well as you Super Tak 1.9) and often folks complain its not sharp. However, I've found with proper MTF software that its incredibly sharp, relative to other lenses like the Tamron SP 90 and the M 100mm. Obviously, I can get incredibly sharp shots with the M 85mm, so some of them are good. I think its lens design is similar to the Super Tak, but I have not shot that with the MTF software.

One obvious problem could be focus, and the way to rule that out is to shoot something like a ruler at a 45 degree angle and see where the true focus occurs, with the lens wide open. My Super Tak can visually seen to be very sharp in the plane of focus, when wide open, without glow or haze (which I see with my M 50 1.4).

A camera repair guy I can personally recommend is Mark at Camserve. He is slow, because he is highly popular. I knew a pro photographer (sadly died recently) who used him and complained that he was slow. However, he was a pro, and chose Camserve. I guess being slow is an indication of being popular and therefore good. With a lens which is expensive and rare, I think it makes sense to send it to someone who has likely fixed it before, like Mark.
Forum: Pentax SLR Lens Discussion 03-20-2023, 02:27 PM  
A comparison of some old 85mm lenses.
Posted By whojammyflip
Replies: 17
Views: 1,852
@wasp, both those photos are lovely, and I would print them and display them, neither is the last word in sharpness, but they are dreamy

with my Pentax M 85, I've found that tripod mounted, its incredibly sharp....its just that using such a lens, its typically a grab shot, portrait, which takes the edge off the sharpness

Another lens with fantastic bokeh at this focal length is the Tamron sp 90.
Forum: Pentax SLR Lens Discussion 03-20-2023, 02:13 PM  
Vintage 135mm Prime vs 135mm@M-Zoom 75-150
Posted By whojammyflip
Replies: 6
Views: 1,130
A great manual zoom for this is the Kiron 70-150, which can be found for cheap....there is one on ebay right now which has been there for months. Its bonkers sharp at the short end.

I tested all my lenses using MTF Mapper a while back, and another sleeper is the Tamron 278d 80-210:

Tamron 278D AF 80-210mm F4.5-5.6 Lens Reviews - Tamron Lenses - Pentax Lens Review Database

it was the sharpest by far of any lens I have at 135mm. Bonkers. Again, you can pick this up for next to nothing. This was against the Vivitar S1's, various Kiron lenses, Tamron SP's, Pentax A/M 80-200, Tamron 135/2.5, Pentax M 135 etc etc.
Forum: Pentax SLR Lens Discussion 03-20-2023, 02:02 PM  
35mm lens recommendations for Pentax MX?
Posted By whojammyflip
Replies: 35
Views: 2,153
Wide open, the M 35/2 is nicer than the M 35/2.8, and has a sufficiently different perspective than the 50mm or the 28mm lenses to justify getting one. Another alternative not mentioned is to get a M42/PK adapter, and pick up a Super Takumar 35/3.5, which is readily available, and a thing of engineering beauty. Its incredible to think these Super Taks are 60 years old.
Forum: Pentax SLR Lens Discussion 03-20-2023, 01:57 PM  
Thank you Simon's Utak Takumar 100mm 1:2 video
Posted By whojammyflip
Replies: 5
Views: 1,362
Its worth getting hold of the "definitive pentax collectors guide" by Gerjan van Oosten, in my opinion....it will probably sell out like the previous version did. It has loads of info on the old Takumars. Even if you use the more modern Pentax primes, its a nice book to look at the evolution of the lens diagrams. These 100's used to have optical formulae similar to the M 85 f2 Sonar lens diagram. The M 100 2.8 split the rear group up, creating a sharper lens. There was a review listed the other day for the Takumar 105, on Vintage Lens Test: Asahi Pentax SMC Takumar 105mm f/2.8.
Forum: Pentax SLR Lens Discussion 03-17-2023, 08:30 AM  
Can't remove a lens!
Posted By whojammyflip
Replies: 26
Views: 9,882
I know, thread resurrection. I just experienced this with an old Sigma zoom. It was not marked as being for a Ricoh mount. I think the particular age of lens to look out for is around 1985, where auto aperture had been introduced, but lenses were still manual focus. Basically, if you have a lens which is auto aperture and manual focus....be cautious mounting it to a camera body with auto focus abilities.
Forum: Photographic Industry and Professionals 02-18-2023, 01:38 PM  
Are used camera and lens prices falling faster than we realize?
Posted By whojammyflip
Replies: 73
Views: 5,870
I was interested as to whether falling prices for Pentax kit had been discussed on Pentaxforums and found this thread. A Pentax DA 40mm went yesterday on Ebay for GBP 75. Strikes me that folks are abandoning Pentax. Its quite sad, I really rate Pentax kit.
Forum: Film SLRs and Compact Film Cameras 11-02-2022, 01:57 AM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
Something to note is that the battery compartments of the SP and the SP1000 are not the same.

The SP has a completely plastic battery compartment bowl, which results in the terminals being better isolated from each other around the sides of the battery. Only the compartment cap and the leaf spring in the compartment are conductive. With the SP, the relative size of the +ve and -ve terminals will therefore not matter. If the positive terminal touches the side of the compartment, because its plastic, it makes no difference.

In contrast, the SP1000 appears to have a bowl which is metallic. The only separation of compartment terminals is the brown plastic at the base of the SP1000 bowl. It will therefore matter how big the +ve battery terminal is. If the +ve terminal touches the sides of the compartment, it may short out.

It looks like the positive terminals on these modern batteries is much larger, forming most of the exterior of the battery, in contrast to the old PX400, which had a small positive terminal, the same size as the modern negative terminal.

The 387s comes with the ring around it to prevent it shorting out, so the only part of the postive terminal exposed is on the base of the battery.

Here is the view of the SP500 and the old PX400 form factor. Note the small positive terminal on the old battery. The old battery negative terminal may have functioned well with a battery compartment made of metal.

Forum: Film SLRs and Compact Film Cameras 11-01-2022, 01:04 PM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
So I have checked the performance of my Spotmatic with Weincell and 392, which just arrived and there is nothing in it. To be honest, I am surprised. I've got a Gossen Lunasix F here, which is a great meter for low light readings.

Gossen: 1/4, f2.2
392: 1/4, f2.8
392, upside down: 1/15, f2.8
Wein: 1/4, f2.8

So you can see, the Gossen would overexpose relative to the Weincell and 392, but the 392 and Weincell, when correctly inserted, agree with each other. I'm half tempted to say, get an external meter.

I think the 392 looks a bit small, although it measures 8x3.6mm. Maybe the slightly larger 394 battery would also fit. But the 390 definitely does not fit my SP. Being subjective, the Weincell gets a steadier response out of the needle, looking optimally damped. Although thats a bit objective.




Nice video. Some quick observations:

- it appears that the SP 1000 battery compartment is in actual fact different to my Spotmatic SP which has a completely plastic bowl, as shown a few posts back. The base in the totally plastic SP bowl is 8.5mm wide, obstructing anything wider than 8.5mm from bottoming out in the base of the bowl.
- at 1min34 in the video, the demonstration of *stopping* down the lens aperture, the needle rises up towards the +, which is in the wrong direction. The reason is the battery is upside down: +ve needs to face upwards into the camera body.
- with a 1.55v battery upside down, exposure is out by 3 stops on my SP....it might also damage the meter
Forum: Film SLRs and Compact Film Cameras 10-31-2022, 05:47 AM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
Its potentially misleading to say the Weincell batteries have only a 3 month life span. Depending on your patience, you can simply cover up the battery holes with the sticker, if you are not using the battery. The shelf life of the battery is 10 years.

https://weinproducts.com/news/entry/istherefinallyareplacementformercurycell...etooksomedoing

---------- Post added 31st Oct 2022 at 12:52 ----------



I think the original PX400 also had a postive terminal which was narrower than the negative terminal. They had a pronounced step shape. So the 392 should actually fit better. The battery has to have a +ve terminal which is narrower than 8.5mm in order to fit into the battery compartment plastic bowl's narrow end.

The ideal battery has a +ve terminal which is < 8.5mm and a -ve terminal which is < 12mm, in order to fit into the battery compartment.
Forum: Film SLRs and Compact Film Cameras 10-31-2022, 02:01 AM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
I've been measuring: My Spotmatic has a plastic bowl shape which requires the top of the battery to be under 8.5mm wide on the positive terminal (facing the camera body). The back of the battery can be much wider, say 12.0mm.

I think the 390 is the wrong shape for the Spotmatic. Its close, but a miss is as good as a mile. The 390 measures 3.1mm deep and 11.5mm wide. The front of the bowl prevents the battery from touching the terminal. Moreover, note the positive terminal should be facing upwards, which is the widest part of the 390. I've tried both and the 390 simply doesnt work for me.

In contrast, the Weincell MRB400 measures 8mm wide, with a rubber washer around the body, taking them up to 11.5mm, so that they fit both in the battery cap, and the battery compartment bowl. Additionally, its 3.6mm deep. It matches the original specification of the PX400.

Looking on old threads on photo.net, others used the SR41 (aka 392) shaped battery with success, although its still 1.55v, which is wrong. That battery is 8mm wide and the necessary 3.6mm deep. My guess is that the 392 will centre due to the battery compartment plastic bowl. I am interested to get to the bottom of this, and have now ordered a SR41 (392). Obviously, this will then result in a battery which has the wrong voltage, but may fit. At that point, I will try different EV light intensities to check out the effectiveness of the bridge circuit in dealing with the wrong voltage, and whether the offset is independent of light value, which is to say, whether a constant offset is sufficient.

I guess my reason for doing this is that I think its a shame for us to not be supporting a company which is providing dedicated batteries. The more we support these companies, the longer they will provide these products. I emphasise again, the Weincell worked straight out of the box, and the metering agrees with both a Gossen Lunasix F and Sekonic L208.

I hope this helps clarify things for others. I've put reference battery specifications beneath, and a link to a prior conversation about this on photo.net from 2003.

https://en.wikipedia.org/wiki/List_of_battery_sizes

Pentax Spotmatic mercury battery replacement - Accessories - Photo.net

Forum: Film SLRs and Compact Film Cameras 10-30-2022, 10:17 AM  
Would you still recommend Eric Hendrickson for a CLA?
Posted By whojammyflip
Replies: 85
Views: 12,630
how does it work when sending cameras across the Atlantic....do folks in the UK have to pay additional taxes to have someone in the US fix up a camera?
Forum: Film SLRs and Compact Film Cameras 10-30-2022, 06:12 AM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
OK, so a couple of Renata 390 batteries just arrived, from Amazon, and they don't work in my Spotmatic at all. The needle doesnt move whatsoever. I'd highly recommend the Weincell if you have a camera body like mine. At the end of the day, its only been 3 quid to test the idea that the Renata battery works, and it concretely does not work in my camera. In contrast, the Weincell works perfectly.

The + terminal on the Renata has to face outwards, as the plastic insert inside my Spotmatic prevents turning them around the other way. In the picture beneath, I have the rear of my camera (note the plastic housing inside, which is bowl shaped), a Renata 390, a Weincell 400, and the battery cover to my camera body. The camera is number 2779604, so its a version 1 and mid series, according to the van Oosten book.

Forum: Film SLRs and Compact Film Cameras 10-28-2022, 07:15 AM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
I've just bought some, and will revert with a comparison of the two.

The Weincell has a rubber ring around it, which can move up and down the battery - I had to reverse the polarity, so that the + terminal faces the body and the - terminal faces the cap....metering is spot on. Surprisingly senstive too, so that I am metering 1/4s f4 @100 indoors....the Sekonic L208 is getting towards the edge of that, so that it nearly cannot measure that light value. Awesome piece of kit. It looks like the Spotmatic I have here has barely been used, the Super Takumar 55/1.8 is spotless. Looking forward to putting in some bulk film and taking some shots.
Forum: Film SLRs and Compact Film Cameras 10-26-2022, 11:12 AM  
Asahi spotmatic sp battery recommendation
Posted By whojammyflip
Replies: 73
Views: 148,906
Why not just buy the dedicated batteries from Weincell? Scanning this thread, it seems to me that "the game is not worth the candle", trying to buy different batteries which may not work.

I've just bought one MR400 battery from the Small Battery Company. GBP 6.5 delivered. I figure that the cost of my time far exceeds the GBP 3.50 saved on buying batteries which are not dedicated. If it runs low in 3 months, I will just buy another.

https://www.smallbattery.company.org.uk/sbc_mrb400.htm
Forum: Pentax SLR Lens Discussion 03-17-2022, 03:55 AM  
Home made MTF comparisons 50mm's, 35mm's, 28mm's and 100mm's + bonus 3.5/135
Posted By whojammyflip
Replies: 8
Views: 2,507
This is great. Its interesting to see the performance of the 55/1.8, the 28/3.5 and the 100/2.8. They all display flat curves as they get stopped down, with the uncertainty bands tightening up.

I tested a boat load of lenses about 3 years ago using MTF Mapper:
MTF Mapper - PentaxForums.com
Forum: Pentax SLR Lens Discussion 03-17-2022, 03:41 AM  
Pentax K 28mm f/3.5 vs Pentax-M 28mm f/2.8 (later version) vs Pentax-M 28mm f/3.5
Posted By whojammyflip
Replies: 29
Views: 5,664
I've compared the M 28 2.8 v1 to the M 28 3.5, using MTF Mapper and a proper test target, mounted on a board etc. The M 28 3.5 was sharper until f8. The 28 2.8 will match it at f8. I think you would only notice the differences in real life, if doing side by side comparisons, any lens on the day would be fine.

Take a look at MTF Mapper for quantifying this stuff:

MTF mapper download | SourceForge.net
Forum: Pentax SLR Lens Discussion 03-17-2022, 03:16 AM  
The mystery of the hazey SMC Pentax-M 100mm F4 Macro
Posted By whojammyflip
Replies: 30
Views: 2,156
I agree, I bought two copies of this, both had it and were sent back to the folks selling it.

I like my Tamron SP 90mm 2.5, which is readily available, produces nice bokeh, and mechanically, its a nicer lens.

For digital I have the DA 35 Limited.
Forum: Pentax SLR Lens Discussion 12-12-2021, 12:14 PM  
Good Lens Hood Recommendations?
Posted By whojammyflip
Replies: 14
Views: 1,098
I just picked up an Ihagee square hood. Its a thing of beauty.
Forum: Film SLRs and Compact Film Cameras 12-05-2021, 05:29 AM  
KX, "special shock absorbers"
Posted By whojammyflip
Replies: 17
Views: 1,585
I saw this place the other day, based in the UK, offering full kits for refurbishment, including camera coverings:

Milly's Cameras - Film Camera Repair Materials and Kits
Forum: Film SLRs and Compact Film Cameras 11-01-2021, 05:29 PM  
KX, "special shock absorbers"
Posted By whojammyflip
Replies: 17
Views: 1,585
The ME Super actually has a pneumatic cylinder which damps the mirror, which the ME doesnt have. Part number 0-B40 in the service manual, labelled as the "shock absorber".
Forum: Film SLRs and Compact Film Cameras 11-01-2021, 05:27 PM  
ME Super light seals?
Posted By whojammyflip
Replies: 33
Views: 15,276
I've purchased kits from Jon Goodman in the past, who just posts them to the UK. I think he can no longer post them with the original bamboo tool though. Highly recommended, precision cut, no light leaks.
Forum: Pentax SLR Lens Discussion 12-30-2019, 07:27 AM  
Opinion time: what are your favorite manual lenses?
Posted By whojammyflip
Replies: 184
Views: 13,989
That second picture, black and white, has incredible sharpness and bokeh at the same time. That looks like an amazing lens.
Forum: Pentax SLR Lens Discussion 12-30-2019, 06:25 AM  
Opinion time: what are your favorite manual lenses?
Posted By whojammyflip
Replies: 184
Views: 13,989
If its the M 28/3.5 and the M 50/1.7, you will struggle to find better. The M 135 is no slouch either. Great set up.
Forum: Pentax SLR Lens Discussion 12-30-2019, 02:53 AM  
Opinion time: what are your favorite manual lenses?
Posted By whojammyflip
Replies: 184
Views: 13,989
My Pentax M 85mm f2 is just incredibly sharp from f4 onwards.

Here are MTF curves from f5.6 at about 4m or 50 focal lengths.

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