Forum: Welcomes and Introductions
10 Hours Ago
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Another plus for your newfound 67 photography is the availability of a lot of used Pentax 67 lenses at a fraction of their original cost. I've bought a few from Japan which I use in my astrophotography, haven't been disappointed in their quality yet. As you say - never too late. Good shooting and your posted photos are great.
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Forum: Troubleshooting and Beginner Help
2 Days Ago
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There are two solutions to this (for the actual shot). You can use a shift-lens (that points at the horizon but shifts vertically to get the subject in the image) or you can use an even wider lens (than what you used in your samples) and keep the center of the image on the horizon. Either will allow you to capture the portion at the bottom of the image without tilting the camera downwards (and the consequent distortion). The latter will require cropping whereas the shift-lens accomplishes cropping in-camera. Also with the latter method, you lose a bit of resolution because of the cropping required, whereas the shift lens uses the full image sensor for all of the image, so no compromises in lost pixels.
Then there is the post-processing method with the great examples previously shown.
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Forum: Pentax K-1 & K-1 II
2 Days Ago
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Does anyone out there know what the microphone input clipping level is (in volts or dBmV) when the K-1 camera is set to its maximum input volume level in movie mode? I'm trying to match it to a particular line level source and need to make an attenuator but am looking for a starting point to shoot for. I know the maximum source level but want to keep that from producing clipping when fed to the camera through an attenuator.
I tried looking in my notes and all over the web but this seems to be an elusive value.
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Forum: Photographic Technique
3 Days Ago
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If you're trying for a handheld shot, holding your breath and bracing yourself against something will help. You can also try the "between heartbeats" thing but that is hard to judge and I usually can't get it right, especially if my heart is racing for the shot. If you have anything stable to put your camera hand up against (fence post, etc.) that can also help. Sitting is a lot more stable than standing and pulling the camera up against your face can help a bit. The longer the lens, the higher the magnification, and the more you need stability. The opposite is also true but you can't cheat by enlarging a shot taken with a shorter FL lens because that also increases magnification, In some cases, it becomes a matter of just reducing the camera shake to the point where its own SR can handle it. If you have too much shake, the camera SR can't move the sensor far enough to handle it.
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Forum: Pentax SLR Lens Discussion
3 Days Ago
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Since you mention that you're in a 95% area, you won't be doing any shooting during totality without a solar filter. Even 95% covered, the sun should be viewed or photographed with a solar filter! It has to be 100% covered if you want to capture the corona or solar eruptions around the edge which is usually done without a filter. Being that you are in a 95% area, what's stopping you from traveling a relatively short distance to the 100% area? That's where all the really good stuff is.
In any case, it will depend on what type of shot you're after as to equipment used.
If you want a close up shot of the sun, you'll be using the longest focal length lens you have (300mm) and even then you need to boost that with your X2 telextender. At 600mm, the image size will still be small in comparison to a full frame (see view approximation below). You WILL need a solar filter for these kinds of shots (not sure by what you mean when you say "cardboard type"). That needs to be an approved solar filter like one you can make from Thousand Oaks material.
If you want to shoot the landscape with the sun in the background, regular lenses will work though expect the sun to be burned out in your shots so you might want to make a composite of a regular shot and one shot with a solar filter.
The key for any of the aforementioned shots is to practice before hand. The sun is out every day. Use the equipment you have and see what works and what doesn't. Plenty of time to practice before the eclipse. You should be able to get an idea of the sharpness of your filtered 300mm/X2 if you can see any sunspots. They make good sharpness tests. Your tripod will prove valuable and don't extend the legs all the way.
If you do go to a location where there will be totality, it's another story. You can't practice and you have a pretty small window of time to get your shot right. You won't be using a filter and you only need to determine what exposure gets a good image. Again, it depends on what type of shot you want - up close or landscape. That determines the lens.
I would recommend shooting in manual and varying the exposure over a range (bracketing). It will be darker than you expect at totality and you may want to use a higher ISO (i.e. 1600) so you can capture the fine features of the eclipsed sun. Don't dwell on the sun when totality ends and don't look at the sun directly without protection except during totality.
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Forum: Film Processing, Scanning, and Darkroom
3 Days Ago
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I have some HC-110 that I pull out every once in a while and it's about 40 years old and still works. I probably wouldn't use it for anything important however as it seems to produce increased grain and maybe a tad of fog.
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Forum: Flashes, Lighting, and Studio
3 Days Ago
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A phone is a poor choice for a lightmeter. As above, it doesn't have the right type of sensor nor the arrangement for the collection of light. The main thing is that it is not calibrated for that use and you probably will get variations from the correct exposure depending on the phone and measured light coloration. Generally speaking, your camera would be a lot more accurate in comparison.
This is a lot like using a phone for audio measurements. It can read sound pressure in dBs but compared to a dedicated audio meter, it will show a lot of errors.
I tested the "level meter" in my phone and the phone was considerably off-level (think bubble level) when the app said it was perfectly leveled. Phones are not precision instruments and are highly overrated for some uses.
Everyone loves "apps" however.
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Forum: Film Processing, Scanning, and Darkroom
4 Days Ago
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Thanks for the links. It appears that the only supply is outside the US and I'm not sure on how shipping to the states would be. I'll keep my eyes open for a US distributor - looks like a good product.
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Forum: Film Processing, Scanning, and Darkroom
5 Days Ago
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Sound's great.
What's the link to a supplier?
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Forum: Pentax K-1 & K-1 II
6 Days Ago
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Are you sure it's "focus related" or could it be that you are submitting at too low a resolution (we can't tell this from your sample photo). What pixel space (horizontal x vertical) are you using for your submitted photos? For example, a K-1 camera has a pixel space of 7360x4912 pixels if the full frame is used. If cropped, you end up with a smaller pixel space and reduced resolution even though you can bump it back up to the original using resampling. Just a thought.
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Forum: Troubleshooting and Beginner Help
03-09-2024, 10:15 AM
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Very likely to be LED lighting and not much you can do about it other than use much longer shutter speeds (mechanical shutter, 1/30s+) which might compromise your shots otherwise. One possible means that might reduce the banding is to use a camera mounted flash that would overcome the ambient lighting.
This is something that affects non-global shutters and can be an issue with most any lighting that contains "flicker" (even a lighthouse shot may need work to capture the light in an "on" state).
As far as post processing those shots you already have, nothing practical will remove the banding, though if you manage to build a negative mask of the banding, you might be able to overlay it on the shots and cancel out the bands, something a bit challenging,
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Forum: Pentax SLR Lens Discussion
03-05-2024, 10:09 AM
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Only one example that I know of that might have presented any "documented" injuries from radioactive lenses. This was in past applications where the radioactive glass was employed in viewing devices in the eye lenses where eye exposure (mostly beta radiation) would happen up close any time the user looked through the eye lens. I don't know if it was anecdotal or not, but I heard historical reports of cases of cataracts being attributed these devices. This is not the same where the lens is out in front of a camera, as the radiation is greatly attenuated with distance and blocked by everything in-between the lens and one's eye when using the camera VF.
I wore a radioactive wristwatch for quite a few years (it giving off as much or more radiation than a lens), and my hand hasn't fallen off yet.
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Forum: Pentax SLR Lens Discussion
03-03-2024, 12:36 PM
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Are you dialing in a small aperture like f22 when you test the lever? You should see the iris close quickly when you toggle the lever. If it's sticking, it should be apparent, and moving the lever should be reasonably easy to do.
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Forum: Pentax SLR Lens Discussion
03-02-2024, 09:01 AM
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Try looking into the lens and take a time exposure (1 - 5 seconds) requiring a small aperture (maybe pointed at the sky over your shoulder). That should give you time to see what is happening with the iris. It is closing at all or making the attempt and not getting there? When you say "manual exposure" are you talking about using the aperture ring on the lens?
Also, it's interesting to note that in your ASIF data, the properly exposed photo was shot at full aperture (like the iris isn't working) and high shutter speed. Was that wide open f-stop specified in your manual setting (second shot) or did you have the f-stop set to another value, and the camera compensated for a stuck iris with a high shutter speed?
Also, you might take the lens off your camera, set it to f22 and move the small lever on the rear of the lens to see if it stops the iris down.
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Forum: General Photography
03-01-2024, 09:00 AM
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Forum: Film Processing, Scanning, and Darkroom
02-29-2024, 09:46 AM
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Most of the process can be replicated but the individual color couplers which formed the yellow, cyan and magenta dyes required specific organic chemicals that Kodak itself once manufactured. The Eastman chemical division was long ago sold off and I don't know if any of it still exists today. Still, there could be some cans of K-14 color developer agents stashed away somewhere, yet to be discovered some day.
It's interesting to note also that those three R, G, and B layers are still in there (in negative form) when Kodachrome is processed as B & W, and contain the information to produce a full color image. It's just that getting to them individually is next to impossible.
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Forum: Pentax Camera and Field Accessories
02-28-2024, 03:18 PM
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A very good video by Christopher Barnatt (check out his others which are mostly electronics related if you have interests that way). Christopher covered all the current types of data storage barring a few that are not commercially available (e.g. writing to glass cubes) and included shortcomings and pluses for each. One thing that came through in this video is that archival storage depends greatly on whether the storage device is in constant use or sits on a shelf. Those in constant use like hard drives are basically wearing themselves out as time progresses. Other media like thumb drives and disc media don't work the same way and have the advantage of more or less static storage although there is still the "bit fade" issue. Personally, right now, I would choose M-disc media if I wanted the absolute best archival storage although Verbatim Gold media mentioned in this video comes in as a close second.
The main thing to be learned from this video is not to trust your SD card for long term storage, so keeping your valued shots on a card located in your camera is not the best idea. Heat and storage conditions are also important for all media types, so attics and cars aren't too kind to data storage in any of its forms and generally if you want to store media, keep it cool and dry for best results
One thing that Christopher didn't mention is storage on multiple devices so a copy is almost always available if one device fails. Those devices ideally, should not be at one location as a large fire or disaster can nullify any advantage multiple device storage in one location might offer (e.g., disc arrays). Storage of Hubble Telescope data is one example. The last I heard, NASA used triple redundancy at three locations for Hubble and backed up the data at each location periodically. Perhaps one of our forum readers has additional info on some of the more exotic means for critical data archiving. For us limited budget photographers however, disc media is good (given the recommendations in Christopher's video) as long as good disc storing conditions are maintained (and one copy in your garage refrigerator for extra measure:)).
Thanks for the video Not a Number!
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Forum: Pentax News and Rumors
02-28-2024, 09:52 AM
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Good shot! Thanks for sharing that one.
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Forum: Pentax K-30 & K-50
02-28-2024, 09:42 AM
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Not the lens Steve. The UV filter is what I was referring to. Any spare UV or skylight filter works and leave the glass in it. You might need a spanner wrench to loosen the retaining ring (or a small piece of sheet metal cut to the right length that would drop in the two indents in the ring and act as a wrench). I dropped a circular-cut piece on the filter material (shiny side away from the glass) on the glass and then put the retaining ring back in. Don't tighten the ring too much or it might crumple the filtering material around the edges - just snug. When you finish, you have a screw-in solar filter that you can keep for future use. Hope that helps.
Good luck!
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Forum: Digital Processing, Software, and Printing
02-25-2024, 02:54 PM
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Quite cool. I'm not sure how well I'd sleep if I had a wolf looking at me like that through the window though??? Hope the glass is extra thick.
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Forum: Digital Processing, Software, and Printing
02-24-2024, 01:01 PM
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Your photo is a pretty tall order for post treatment. Of course it depends on the extent of the reflection but your has quite a bit to clean up. AI would probably be your only hope short of taking a very long time to carefully air-brush the reflections but that probably wouldn't give you very satisfying results. Here's my 2 cents worth of "AI" (actually just some manipulation of the original in Photoshop). Still not the best but I rushed it so you might be able to do better given some work time.
If you had the camera locked down and then placed a dark sheet on the outside of the window allowing you to catch the exact same reflection, you could subtract that in post and come up with something presentable, but of course that isn't possible where you are now.
Next time, you need to get as close to the glass as possible and have all room illumination killed which will help.
Very interesting that the wolf would come up to the window that close and check you out and it would have made a great shot. It's still a really good shot showing the window with the wolf gazing in.
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Forum: Pentax K-30 & K-50
02-24-2024, 08:51 AM
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Yes, The Thousand oaks filtering material I got was approved for both visual and photo use and that's what I made my binocular filters out of. I used two peanut jar lids which fit snugly over my binoculars and cut holes in each. I have access to a 3D printer and printed two rings which I cemented the filtering material to and then inserted and cemented those into the peanut jar lids.hold the filters in place. Good luck on your solar adventures.
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Forum: Pentax K-30 & K-50
02-23-2024, 09:38 AM
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Be sure to get the right solar filtering material for those binoculars. There can be a difference between "visual" and "photo' filtering grades. If you're looking through binoculars, you definitely want to be safe. Some material that works for photo use may not fit that requirement.
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Forum: Troubleshooting and Beginner Help
02-22-2024, 04:46 PM
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It might be helpful to know what the substance is. I would first "attack" it with a cotton swab lightly dampened with distilled water and see if that will dissolve the substance.Use circular sweeps while rotating the swab and don't use any significant pressure - keep the contact as light as possible. If the substance is water soluble, it should come off. If you feel any "grittiness" at all, stop and blot any moisture with a lens tissue by laying the tissue on the surface, and then "pealing" it away with the moisture. You don't need to get it all and it should evaporate without leaving any trace.
If you see any success with the first swab, you might have to change out swabs with clean lightly dampened ones as they soak up the residue (assuming this works on your substance). Work slowly and carefully.
The key here is not to apply pressure and proceed carefully (try one small area to begin with).
If water doesn't dissolve any of the substance, you'll have to try something a bit more aggressive................
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Forum: Pentax K-30 & K-50
02-22-2024, 09:46 AM
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There are mounted solar filters out there but you might end up making your own (especially handy for large filters). Be sure to use a good material like that from Thousand Oaks. You can cut this and place it in a UV filter mount (be sure the filter material covers all the light path with no leaks). Unscrew the retaining ring and drop your cut filter in shiny side facing away from your camera, and replace the retaining ring. Here are some sources from Amazon. Note, never use polarizing materials (shown on this page). They allow infrared light to pass, which can cause shutter/sensor damage (and eye damage if using an optical VF). Use only approved filters or filtering material. https://www.amazon.com/s?tag=pentaxforums-20&k=solar+filter+sheet&crid=Z8O7D..._ts-doa-p_2_12
If you will be shooting at high magnification (close up shots of the sun), you need a steady mount and good lens. Use electronic shutter if possible with an electronic shutter release. These will greatly help with vibrations. Liveview will also be handy as it allows you to focus better and you can see exactly what you're shooting. Practice before the event!
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