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Forum: Pentax Full Frame 11-24-2020, 09:43 AM  
How much mental adjusting would it take moving from APC-S to full frame photography?
Posted By lister6520
Replies: 63
Views: 4,607
The only readjustment I need is because of using APSc lenses with the K1. Most of them fill quite a bit more than the APS-C size but not quite the full sensor. Because of that I tend to set the camera always to full frame and then I'm supposed to remember to allow for the vignetting but far too often I forget about that and end up with a photo that I have to crop smaller than the composition required so as to get rid of the cut off corners.
Forum: Photographic Technique 11-20-2020, 06:51 AM  
Astro O-GPS1 + K3 + Dobsonian ???
Posted By lister6520
Replies: 12
Views: 1,106
Something I found with regards to the tracking accuracy is that it is not the only thing that matters. It is also important to have a magnetically 'clean' environment. The calibration can only compensated for the local magnetic variations caused by the camera itself and anything directly attached to it, such as the lens and the quick release plate. Any other local variations cannot be accounted for and will result in an incorrect North.

The worst causes of such uncorrectable variations I have encountered are rebar in concrete structures, especially if standing on them such as on a building or even a concrete pavement and nearby cars. By nearby I mean within less than about 10 meters (30 feet) or so. Other hidden things such as buried steel pipes, metal fences and such can all through off the compass enough to cause significant trails.

Something that may also make a big difference is the tripod itself, or the telescope, as those obviously cannot participate in the calibration dance. Sometimes it could be easily fixable such as replacing some steel screws with brass ones if they are the only magnetic material but if there are other structural parts that are ferromagnetic it might not be possible to sort out.

Finally make sure to keep away any flashlights, cellphone, tablet or other electrical/electronic devices as even the small currents flowing through them can cause a detectable shift in the magnetic field around them. Some devices even have magnetic catches on their cover.

When I first used Astrotracer I struggled to get trail-less stars at long focal lengths until I started discovering what was interfering with it. Shooting from home is still impossible due to the rebar in the roof which i quickly figured out but out in the open it had taken me quite a while to discover first the bad influence the tripod was having and after fixing that (by using another tripod) I found that moving the car a bit further away from where I stood sorted it out and I could get one minute exposures without trails using my Sigma 150-500. I think by extrapolation one would be able to get minimal trails or with some luck not at all even at 2000mm if one is extra careful in avoiding any magnetic interference.
Forum: Pentax K-r 11-17-2020, 11:33 AM  
Bought a Kr
Posted By lister6520
Replies: 8
Views: 1,768
Apparently it is quite easy to fix the aperture problem on the K-50 and some other Pentax cameras. I have on occasion come across videos on Youtube explaining how to fix aperture solenoid problems on Pentax cameras though I don't remember exactly which models.I think it would be well worth giving it a try.

The K-r by the way was my first DSLR and my first Pentax, though not my first K-mount camera. I eventually upgraded to K-30, K3 and now K-1ii but there were a couple of things the K-r had that were better than any of the later models, two in particular being the side by side image comparison and more importantly very good sensor based stabilization for video, which sadly they abandoned in later models opting instead for a near useless digital stabilization they refer to as Movie-SR.
Forum: Flashes, Lighting, and Studio 11-17-2020, 11:23 AM  
Source for new capacitor Metz 58AF2?
Posted By lister6520
Replies: 16
Views: 1,670
It is normal for electrolytic capacitors to not function after a long time of not being used but it does not mean the capacitor needs to be replaced. Ideally one removes the capacitor and reconditions it. Typically this is done by applying its rated voltage across it through a resistor and leaving it for a considerable length of time, maybe even a couple of days for a capacitor that hasn't been used for many years.

However I've had some old flashes that I had not used for a very long time and I managed to get them to work simply by leaving them switched on continuously and replacing the batteries when they run down. Eventually the capacitor does charge up, sometimes after having gone through several sets of batteries. Once it does it at first has low light output but several charge/discharge cycles bring it back to working properly.

I suggest you try this before going through the trouble of dismantling the flash and getting a new capacitor. Generally unless the capacitor has visibly leaked its electrolyte it will not be faulty and would just need the reconditioning. Electrolytic capacitors do fail a lot in electronic equipment but those are ones that are used continuously at high temperature rather than ones that are not used at all. Almost always when an old unused capacitor appears faulty it just needs reconditioning.
Forum: Pentax Medium Format 11-16-2020, 05:16 AM  
CCD Advantage??
Posted By lister6520
Replies: 22
Views: 3,111
I think the CCD better than CMOS thing is mostly due to the fact that CMOS sensors were first designed as a cheap alternative to CCDs and carried an undeserved reputation of being inferior even when they surpassed CCD in practically all respects.
There is really only one difference between CMOS and CCD that matters and it is the way the information is read out, with CMOS having the advantage of not suffering from blooming (bleed between pixels on the same read line) and some inherent advantage in signal to noise ratio (because the readout process is more direct). All the other differences are either related to reducing the cost of the manufacturing process or simply other technology improvements have been brought about with time and that could actually be applied to CCD sensors as well if one wanted to.
So apart from the blooming and slight difference in noise, most comparisons between CCD and CMOS are just comparisons between sensors of different technological maturity rather than inherently of them being CCD or CMOS.
Forum: Photographic Technique 11-16-2020, 05:07 AM  
Astro O-GPS1 + K3 + Dobsonian ???
Posted By lister6520
Replies: 12
Views: 1,106
It won't work with a dobsonian but would work fine with a cassegrain or similar arrangement having the camera facing the same direction as the telescope. The exposure time would be quite limited due to the long focal length but stillnot too bad, about 30 seconds for a 1500mm focal length. Also, the maximum focal length it can accommodate is 2000mm, at least on the K1-ii, other models may have different limits.
Forum: Pentax Full Frame 11-16-2020, 05:06 AM  
K-1 locked up
Posted By lister6520
Replies: 9
Views: 1,012
I've had my K1-ii for a few months now and it has done that a few times, though to me it happened during pixel shift shots and some times just in live view without shooting any picture. A couple of the times I had to leave the camera without battery for several minutes for it to recover as just removing it and reinserting after a few seconds wouldn't bring it to life. It would just make a loud click sound the first time the switch is turned on and then nothing happens.

Whether by coincidence or not I noticed that each time it did it I was using a rather old third party battery which I had bought for the K3 many years ago. I think this is in line with what Adam said about voltage dips.

I have since stopped using that battery on the K1-ii and haven't seen the problem again. Curiously that same battery still works fine on my K3, perhaps it is less demanding on the battery.
Forum: Pentax DSLR Discussion 10-21-2020, 02:32 PM  
Lack of GPS
Posted By lister6520
Replies: 22
Views: 1,947
The GPS frequencies are entirely free from other legitimate communication signals. The keyword here is legitimate. It is easy for faulty or poorly maintained transmitters to emit unintended frequencies that interfere with GPS. These unintended frequencies would be much weaker than the intended signal but if you are close to the transmitter it is enough to block the GPS signal. The standard GPS signal is actually very easy to block, whether intentionally or otherwise as it is very weak and not spread very widely across the spectrum. Being close to radio transmitting stations, PMR repeaters or anything else that transmits in VHF and UHF will easily block it.

Depending on where you are you could even be experiencing deliberate jamming. In Libya for instance last year jamming was used extensively and its effect was felt far beyond the intended area blocking GPS receivers on high ground even as far away as Malta and Sicily.
Forum: General Photography 10-21-2020, 02:18 PM  
The Iphone 12 is better than a DSLR
Posted By lister6520
Replies: 323
Views: 19,022
I don't know about the iPhone but my good old Samsung S6 is way better than the K1-ii. I haven't yet managed to make one single decent phone call on my K1-ii despite meticulously studying the manual cover to cover three times.
Forum: Digital Processing, Software, and Printing 10-21-2020, 12:56 PM  
What software do you use to post process your photos?
Posted By lister6520
Replies: 199
Views: 13,491
I've just checked again now. I used exif-tool on the original DNG of a picture that has tags in lightroom and I do not see the tags anywhere in the original DNG.

In the exported files I do find the tags as expected, both if I export as DNG as well as if I export as jpeg.
Forum: Photographic Technique 10-21-2020, 09:42 AM  
How to track fstop and shutter speed when shooting film or vintage lenses on digital?
Posted By lister6520
Replies: 27
Views: 2,181
I would suggest a small audio recorder, a digital equivalent of a microcassette recorder. You can of course do the same with a smartphone but that is very fiddly and impractical unless you are shooting at a very leisurely pace and don't mind that. With the digital recorder there is just one button to press and then you speak the frame number, time and settings. SOme recorders will also automatically timestamp and they are small as a keychain so you can even hang it on the camera strap.

Alternatively a tiny keychain camera could also be used. Again this would need just one button press, or possibly two if it doesn't switch on automatically on pressing the shutter button. You could just take a photo of the top of the camera showing the exposure settings and even which lens is mounted. A second photo replicating approximately what you shot would also be helpful to make sure the pictured settings are of the actual photo they are meant to belong to. I've occasionally used such a camera attached to the camera strap when using adapted lenses. It is way more convenient than using the smartphone.
Forum: Digital Processing, Software, and Printing 10-21-2020, 09:28 AM  
What software do you use to post process your photos?
Posted By lister6520
Replies: 199
Views: 13,491
@DMS, AFAIK the raw files are always safe as Lightroom doesn't touch them so even in worst case if Lightroom becomes completely inoperable your raw files will still be there. What you will lose is all the processing work you did on the files, the cataloguing and classification etc. Whatever you do with lightroom it leaves the original raw files alone and stores the changes separately in that catalogue. It does not even ad the tags to the raw files. I also regularly backup up the hard-disks so even if something does happen the raw files I will only lose the last few. Even so I generally only delete the raw files from SD card after I have done the backup, so if the hard disk gives up before I made a backup I still have the originals on the SD card.

To protect also your processing work just make sure you export the pictures after processing them, even if just as jpeg. You will not be able to go back to re-edit them but you will at least have the result of your hard work.
With regards to cataloguing you will also partially save your work by exporting jpegs as they will contain the EXIF tags which preserve much of the information needed to catalogue them in some other application. If you had not exported the photos you will lose all the tagging information as LR doesn't write the tags into the exif of the original raw file but it does write them into the files it exports. So any other application that can catalogue photos based on tags will work with the exported photos.
Forum: Digital Processing, Software, and Printing 10-20-2020, 11:00 AM  
What software do you use to post process your photos?
Posted By lister6520
Replies: 199
Views: 13,491
Lightroom Classic. I use not just for RAW processing but also for classifying and cataloguing the photos. I also use an ancient PaintShop Pro for some retouching and post processing but I'll be switching over to Photoshop since that came 'for free' with Lightroom once they started charging monthly subscription.
Forum: Troubleshooting and Beginner Help 10-12-2020, 07:32 AM  
Grainy viewfinder
Posted By lister6520
Replies: 6
Views: 1,526
The graininess is due to the narrow aperture. You will see the same also on shorter lenses if you stop down the aperture (with the DOF preview lever), but to a lesser extent. What happens is the light strikes the focus screen more parallel at narrow apertures and this brings out the grains of the 'ground glass' focusing screen.
Normally it is not very visible at wide open but super zooms are narrow even wide open. Also make sure the aperture blades are actually opening fully as they could be jammed.
Forum: Mini-Challenges, Games, and Photo Stories 10-09-2020, 02:47 PM  
Photo Scavenger Hunt Game Continued - Part II!
Posted By lister6520
Replies: 20,916
Views: 1,108,748
Red sand and rock granules. Let's see some bigger rock granules though, perhaps even boulders..



https://dl.dropbox.com/s/gyo3g4b3q38pbz0/PK3_7580.jpg
Forum: Pentax K-1 & K-1 II 10-09-2020, 12:26 PM  
Is there an onboard battery - and is mine running out?
Posted By lister6520
Replies: 12
Views: 1,325
I have a K-30 and a Q10 with that problem, but they're about 8 years old. My K-3 (age 7) is still OK until now. My K1-ii is just months old so no problem there for sure.

Since quite a few years ago I stopped leaving the camera without a battery precisely to avoid this problem, in other words whenever I remove a battery to recharge I immediately replace it with another one to avoid discharging the clock battery. It may be why the K-3 internal battery still works long after the K-30' battery gave up.

It is quite a problem if you're going to leave the camera unused for a period of months as it is usually advisable to remove the battery from equipment that is not being used for along time but doing that will probably ruin the internal battery rather quickly.

I'm also wondering if by not replacing the faulty internal battery it might end up leaking acid and ruining the internals of the camera, as often happens with desktop PCs that are left unused for a period of time.
Forum: Pentax K-1 & K-1 II 10-09-2020, 12:16 PM  
Silver K-1 - disabling guide display
Posted By lister6520
Replies: 8
Views: 1,242
Are you sure, does Pentax even make that many cameras of all models in total?
Forum: Pentax K-1 & K-1 II 10-09-2020, 12:12 PM  
It’s Here!
Posted By lister6520
Replies: 16
Views: 1,930
I've long suffered from GAS but until recently I seemed to be immune to the LBA strain. Just lately I realize I caught a particularly bad strain of LBA ending up with a bunch of almost adequate lenses that look decent in a display cabinet but don't do a particularly good job of taking pictures and a much lighter bank account.
Forum: Pentax K-1 & K-1 II 10-09-2020, 12:02 PM  
Optical stabilization in video with Sigma 150-500
Posted By lister6520
Replies: 3
Views: 901
It was something that just occurred to me out of the blue so to speak, it must have followed on from something else I was thinking about but I've no idea what that was. I just thought that since the stabilizer is normally activated by half press of the shutter (intended to have it ready by the time the shutter is released) then maybe it would activate also with the focus back button when autofocus is turned off, whether it would do so also in video and more importantly if it would stay active or just turn itself off again after a few seconds. A couple of days later I tried it and it worked just as I thought it might.

In the meantime I also discovered a disturbing problem with the in lens stabilization for still photo shooting that perhaps explains many blurred photos I got with this lens when using the in lens stabilization instead of the in-body. When using the back button focus (so half press doesn't focus) the shutter half press does not activate the stabilizer in the lens. I always use the back button and very often pre-focus with it and then shoot several shots without refocusing (because the subject would not be changing distance). The problem I now realize is that a few seconds after releasing the focus button the stabilizer deactivates meaning that all shots after that will be unstabilized.

I have often stated that I get more reliable results with the in body stabilization than the in lens and now I'm wondering whether this is the reason rather than an actual difference in performance between the two, and I don't know how it took me seven years to realize this. I think this more or less rules out using the in lens stabilization in conjunction with back button focusing in most situations.

---------- Post added 10-09-20 at 09:03 PM ----------

PS: I just tried it with the K-3 and it seems to work exactly the same as the K1-ii.
Forum: Mini-Challenges, Games, and Photo Stories 09-27-2020, 06:12 AM  
Thematic Street Photography (No, Not THAT Street Photography) - Share Your Shots of the Roads
Posted By lister6520
Replies: 5,337
Views: 372,642
It's across a wide and shallow valley. I was on the same road at the opposite side of the valley a little under a Km back.

This is where I was: 35.955910° 14.349151°
This is the part of the road you see in the picture: 35.962794° 14.344756°
(just paste the coordinates in the seach box of Google Earth)
Forum: Pentax SLR Lens Discussion 09-27-2020, 04:07 AM  
Pentax 28-200 won't focus to infinity
Posted By lister6520
Replies: 2
Views: 784
I recently purchased a used Pentax SMC-FA 28-200 IF AL and found it to be better than what I expected from reviews except for one major issue. It will not focus to infinity at focal lengths of less than 100mm, getting worse as the focal length decreases. At short subject distances it's fine and in fact it took me a while to notice the problem as I had been trying indoors and getting good results until I finally got the chance to go outdoors and shoot some pictures with it.

I have seen mention of autofocus issues with this lens and its Tamron brother, however here the issue is not autofocus but that the lens cannot actually bring infinity into focus. At 28mm the furthest focus distance is about 20 metres. It feels as though the focus ring should just be able to rotate another couple of mm to bring infinity into focus.

It is not a matter of poor sharpness at short focal lengths either as it gives reasonably sharp images at closer distances whereas the distant ones are hopelessly blurred. The first image attached below is the one shot at 28mm. The second one is scaled down from a shot with the same lens at 200mm. It is scaled to 14% to match the same pixel size as the 1:1 crop of the 28mm shot. The last picture is a 1:1 crop of the photo at 200mm showing very good sharpness.

Has anyone had similar issues with this lens, or others, and perhaps managed to repair it? I think the actual adjustment would be quite simple and I'm quite confident I could do it but what I dread is disassembling the lens and reassembling it properly without breaking anything or messing up some adjustment. I tired to look for some guide on youtube and elsewhere on how to disassemble/reassemble but I've come up short.
Forum: Pentax K-1 & K-1 II 09-27-2020, 02:08 AM  
Optical stabilization in video with Sigma 150-500
Posted By lister6520
Replies: 3
Views: 901
I've just figured out a way to use the optical stabilization of my Sigma 150-500 for video. At first sight it seems to work almost as well as the sensor stabilization did on the K-r and might make video usable for me on the K1-ii.

I set up like so:
Movie SR - off
Camera set to manual focus
Focusing with back button (not half press shutter)
Lens AF on
Lens stabilization Mode 1

Now while shooting video if I press and hold the AF button the stabilizer is activated and remains active as long as I keep the button pressed. The stabilization is good and definitely helps a great deal, even if not as good as the ancient K-r was with sensor stabilization, and presumably still is unless they ruined also that with some firmware 'upgrade'.

I tried it out handheld at 500mm in this video. The video starts without stabilization. At 00:05 stabilizer activated and continues to be active, at 00:32 it is turned off and then at 00:50 I turned it on again. You can hear a loud 'clunk' when the stabilizer is activated/deactivated, i think it is the mechanism that locks it in place when turned off.

Dropbox - IMGP4726.MOV - Simplify your life

Next, out of curiosity, I tried to see what happens if I also activate the dreadful Movie-SR. Surprisingly it seems to work very well in conjunction with the in lens stabilisation as it now has to correct only for much smaller movement and causes no jello effect. This is possible because the Movie-SR doesn't use the gyroscopes so it won't be undoing the work of the in lens stabilizer as would happen when using IBIS in stills.

I'm still not sure if it is better with both systems on or just the in-lens. This next video is with Movie-SR on and again turning on/off the in-lens stabilization. It starts with in lens stab off, then turned on at 00:03 and off again at 00:48. The Movie-SR on its own is unusable as can be seen after 00:48 where it is worse than the unstabilized sections of the previous video. When in conjunction with the lens stabilization it is both better and worse. There is some jello effect but it is quite small but in compensation the image becomes almost rock steady.

Dropbox - IMGP4728.MOV - Simplify your life

Of course holding the AF button for any length of time is not very practical but if the same works with the focusing set to half press of the shutter button (which I haven;t tried yet) then its just a matter of modifying a remote shutter release so it can lock in half press. That will be able to keep the stabilizer on indefinitely without having to hold anything.

The 150-500 is the only lens I have with built in stabilization. I am guessing it will work the same with other stabilized lenses as well.
Forum: Mini-Challenges, Games, and Photo Stories 09-27-2020, 01:27 AM  
Thematic Street Photography (No, Not THAT Street Photography) - Share Your Shots of the Roads
Posted By lister6520
Replies: 5,337
Views: 372,642
Thanks for letting me know. I added another link - this time it is much shorter, I don't know why but I'm hoping it will work.

Is it only the link to the full size image that is not working or does even the preview not show up?
Forum: Mini-Challenges, Games, and Photo Stories 09-26-2020, 12:27 PM  
Thematic Street Photography (No, Not THAT Street Photography) - Share Your Shots of the Roads
Posted By lister6520
Replies: 5,337
Views: 372,642
Forum: Pentax K-1 & K-1 II 09-23-2020, 02:14 PM  
continuous shooting question on K 1 II
Posted By lister6520
Replies: 5
Views: 961
In theory it should be twice as fast if writing jpegs alternately to the two cards but for some reason it is instead slower. It seems like it is for some reason unable to write simultaneously to both cards. I don't know if that is some hardware limitation (maybe a single SD interface multiplexed between the two cards instead of two separate ones?) or perhaps just some limitation in the firmware that they could fix in a future update.
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