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Forum: Pentax DSLR Discussion 2 Days Ago  
And people wonder why DSLR sales are declining...
Posted By Bob 256
Replies: 120
Views: 2,749
This sound's like a lot of sour lemons from a cell phone user. Comparing phones to SLRs is not exactly a science (to say it lightly). The two just don't compare.

For one, I don't want to stop in the middle of a shoot and put my camera on a wired OR wireless charger and wait for it to charge before I can use it again. Replaceable batteries allow just that - reloading without any need to wait. With spare batteries, there is no need to carry a charger nor a need for 110 VAC to recharge.

I do have WiFi with my K-1 and although it's slow, I rarely use it to transfer files. I have downloaded phone files and it's no faster once the phone is connected to a computer (in fact an SD card will usually download faster).

Just think twice before condemning the "lowly" DSLR to history. It has a lot to offer beyond cell phones for the professional and advanced photographers out there, or they would all be using cell phones for their cameras.
Forum: Pentax SLR Lens Discussion 12-04-2018, 11:10 AM  
Questions about T mounts / T adapters
Posted By Bob 256
Replies: 12
Views: 528
Basically there are the two parts as you indicated. The camera adapter in your case would be a K adapter which has the K mount on one side and a female T thread on the other. The second part is the telescope adapter which has a male T thread on one side and the tube which goes in your eyepiece holder (1.25 or 2 inch slide fit) on the opposite side. The ones you mentioned should work.

Having the first part lets you use any accessory which has the male T thread. That includes other adapters and some lenses. The downside to a T adapter is there are no mechanical or electrical connections to the camera so everything is manual (aperture settings, etc.) if you use the adapter with a lens. Of course with your telescope, the aperture is fixed so there is no need for coupling to the camera. You have aperture priority operation and select exposure using the shutter speed.
Forum: Troubleshooting and Beginner Help 11-30-2018, 02:22 PM  
Cleaning fingerprint on mirror
Posted By Bob 256
Replies: 9
Views: 683
That's the same technique for cleaning astronomical mirrors in telescopes and should work for you. The key thing is avoid anything that could have grit or residue in it so be sure to use lens cleaning tissue and good ethanol. Good luck.

PS: The sooner the better since the fingerprint can have acid in it which can etch the aluminum coating and leave a permanent mark.
Forum: Pentax K-01 11-22-2018, 04:17 PM  
k-01 asking for date every time I turn it on
Posted By Bob 256
Replies: 18
Views: 652
By "doomed to a repair job", I mean that at some time (in the case of the OP it wasn't that long) the RTC will fail and require a repair unless one likes to reset the clock every time a main battery is removed.

"Accumulator cells" are a better way to go. They are sometimes referred to as "super caps" or the like and are really just a capacitor of high capacity which charges off the main battery and allows it to be changed out without losing the clock operation, but accumulator cells can go bad as well (though less likely than a lithium backup cell). In either case, a failing cell can be a consternation.
Forum: Pentax K-01 11-22-2018, 10:55 AM  
k-01 asking for date every time I turn it on
Posted By Bob 256
Replies: 18
Views: 652
User settings are often stored in flash memory which doesn't need battery backup, but the real-time clock (with the exception of a few chips which have a built-in cell) requires constant power to maintain its function and time keeping. That zoom function - I don't know. I would think that would go the same place as the user settings but????

Most battery back-up cells are soldered in but if accessible, are easy to replace. If you decide to replace your camera, I would go on-line and see if there are any guides to K-01 disassembly and pop the cover. If you can locate the battery, it should be an easy fix if you have any soldering skills. You might have to go to Mouser or Digi-Key to locate the proper cell. Usually they are lithium and often they don't get a charge from the main battery but just have a long life in this application (unfortunately no long enough in your case).

I used to be frustrated with multi-thousand dollar pieces of test equipment which had internal coin cells. It would seem that there would be a better way. For time-keeping clocks though, it's almost a necessity.

I'm using a computer which has an internal cell, and it has been good for over 18 years now (knock on wood). I have another which needs a coin cell change every two years. It's unfortunate to know the K-01s and perhaps even the K-1s are doomed to a repair job (or replacement) for this reason. Something my old film camera wasn't subject to.
Forum: Pentax K-01 11-21-2018, 03:36 PM  
k-01 asking for date every time I turn it on
Posted By Bob 256
Replies: 18
Views: 652
Definitely sound's like the memory battery which is internal. Actually, it shouldn't be that hard to get to for a repair tech. I would try to get a quote before I gave up or went seeking a camera replacement. Just out of curiosity, how old is your K-01?
Forum: Pentax SLR Lens Discussion 11-21-2018, 10:46 AM  
Damaged SMC 50/1.2 on eBay starting at $9.99
Posted By Bob 256
Replies: 16
Views: 677
A good clean lens for sale. I used to keep it in my coveralls until my wife ran it through the washing machine and threw it in the spin dryer. No mold (yet) or dirt and still focuses (pretty well).
Forum: Pentax K-01 11-21-2018, 10:33 AM  
k-01 asking for date every time I turn it on
Posted By Bob 256
Replies: 18
Views: 652
I'd try another battery you know is good and with that battery in, perform a firmware update with the latest firmware you have available (or get the last one from Ricoh off the internet). If that doesn't fix the issue, it's time for a repair at the shop. I would go ahead and enter the correct time and date if it allows you to. I don't know if the K-01 has an internal battery to power its boot & time system like some computers do, but that sound's a lot like what happens when one of those runs down in a computer.
Forum: Pentax K-1 11-13-2018, 06:00 PM  
Electronic Shutter Exceptions (Bug?)
Posted By Bob 256
Replies: 22
Views: 932
That too. Guess that's what I was alluding to but didn't directly say it in those terms.
Forum: Pentax K-1 11-13-2018, 11:08 AM  
Electronic Shutter Exceptions (Bug?)
Posted By Bob 256
Replies: 22
Views: 932
Specifically turning on the electronic shutter while in the OVF mode doesn't make too much sense since using it in that mode would be a wasted effort since the mirror has to flip up and return for a shot. That pretty much nulifies any vibration or noise advantage the ES has. This might explain the rationale for not giving shortcut access to it in the OVF mode.

As has been said, it can be turned on with a menu option and left that way, but be forewarned that image artifacts can result with moving subject matter. It is best used on static shots such as landscapes and the like.

This pretty much relegates EF use to mirror lock-up (live-view) use where it can be selected or deselected via the INFO shortcut.
Forum: Digital Processing, Software, and Printing 11-10-2018, 03:48 PM  
Setting up HDD for reliable read/write access from both Windows 10 and Ubuntu / Mint?
Posted By Bob 256
Replies: 24
Views: 744
The issues I've had with FAT32 deal with recording video and pose a size (time) limit on how much can be continuously recorded. Some video authoring apps can be limited or excluded by that limit. It's one of the K-1 camera issues since the SD cards are FAT32. Otherwise, as you said 4GB is a BIG file and you shouldn't run into issues with most other types of applications.
Forum: Photographic Technique 11-10-2018, 11:37 AM  
Why would you use these values for taking a picture?
Posted By Bob 256
Replies: 13
Views: 904
1/focal length only applies if you have a good grip on the camera and are standing on firm ground to begin with. A rocking boat knocks that number down considerably, so 1/8000 isn't that all unexpected. The only issue 1/8000 creates is very little light for the sensor to work with (when combined with the TC which multiplies the lens f stop as well) - a reason to boost the ISO.

It may be that the zoom lens being used performs better at the shorter focal length with the TC than at that same focal length zoomed. I have a Sigma 55-500mm in which that's the case for its upper zoom range. Of course, the TC has other issues, but it may have been attached to allow a longer reach and then there was the bear. I might opt for that shot rather than try to get the TC off.
Forum: Pentax SLR Lens Discussion 11-09-2018, 12:03 PM  
Getting into Anamorphic lenses on a budget?
Posted By Bob 256
Replies: 5
Views: 516
RKKS08's advice was good. If you find a lower cost anamorphic lens (or adapter), not only will image quality be poor but expect a lot of color fringing. Projecting those images will require the same lens adapter on the projection lens (though printing can be accommodated with software) and that means even more image degradation. All in all, anamorphic lenses aren't worth their issues unless your use is professional cinema (big $$$$ lenses). Wide angle lenses of excellent quality are available today which work very well if you want high aspect ratio photos.

Everything I've seen anamorphic is way North of $200.
Forum: General Photography 11-07-2018, 11:44 AM  
High resolution, less leeway for exposure?
Posted By Bob 256
Replies: 15
Views: 757
I don't disagree with what you're saying. More pixels will contribute to the "dither" of the original single pixel space since the noise element in each is random, however the randomness from the actual value that pixel space should have is larger (higher signal noise) for each of the smaller pixels. I'd have to open my statistics book to see how these would combine, but I believe you are correct in saying that four pixels added (actually averaged) with more noise (and that noise won't be twice the single pixel noise) will contribute to a better image, both noise and resolution wise.

There does come a point however, where reduction in the size of the pixels so much starves each one for light, that performance will fall off considerably. I have no idea if modern cameras are at that point yet (apparently not since the K-1 is such a great performer).
Forum: General Photography 11-07-2018, 08:31 AM  
High resolution, less leeway for exposure?
Posted By Bob 256
Replies: 15
Views: 757
I probably should have qualified my example. I was talking about effects over a single sensor technology. Different technologies can have improvements (like making a sponge with finer texture) resulting in sensors with less noise than others. That leads to the ability to throw more amplification at a sensor and not get as much noise (or dynamic range reduction) as a comparative sensor. Just look at sensors from 10 years back and compare those to the K-1 sensor we have today. However, if we talk about just one sensor technology, generally speaking, denser and smaller (not necessarily more) pixel sites lead to poorer sensor performance.

If the exact same pixel technology as exists in the K-1 were used to create a 144Mpx sensor by shrinking the pixel sites (same sensor size overall), one would expect worse performance (higher resolution however). Crop that sensor to get back to the 36 Mpx K-1 resolution, and the decrease in performance would remain (with a sensor which is physically smaller). (This all assumes the 36 Mpx pixel architecture could be shrunk by a factor of two to get 144Mpx).
Forum: General Photography 11-06-2018, 04:23 PM  
High resolution, less leeway for exposure?
Posted By Bob 256
Replies: 15
Views: 757
When smaller pixels are used, less light is received by each pixel. This can be compensated for by amplifying the output signal more but that's about the same thing that's done in raising ISO for a given sensor, so dynamic range suffers as mentioned previously. You also raise the noise levels. Think of a sponge that's 1 inch think. It has a certain grain to it. If that sponge is cut in half but is stretched to fill the 1 inch thickness as before, the "grain" increases. The amount of noise limits what can be brought out of the shadow areas so less shadow information can be retrieved when the sensor is starved for light and the signal is amplified to compensate. Smaller pixels - less light per pixel (for a given image size).
Forum: Pentax K-1 11-06-2018, 08:29 AM  
K1 with Remote Release - Auto Focus Failure
Posted By Bob 256
Replies: 7
Views: 513
Probably what has been suggested, but just in case: If you're using the O-RC1 IR remote, it uses a separate button for the autofocus function. In that case you need to hit that button first (to focus), and then the shutter release. Handy since it allows you to leave the AF with remote activated, and choose whether to autofocus or not. I believe some other IR controls work the same way.
Forum: Pentax DSLR Discussion 11-03-2018, 02:04 PM  
K1 GPS and Compass
Posted By Bob 256
Replies: 3
Views: 540
Since the stars and constellations move with time, they have their own coordinate system (which also moves relative to earth coordinates with time). The K-1 gives pointing direction fairly accurately, so if you had a sky reference to relate the position of a sky object to earth coordinates at that time, you could roughly locate them using the K-1 compass. The elevation is not so straight forward however, as has been pointed out, and you would have to approximate that or have a calibrated mount to get to the object of interest.

The K-1 helps but you could probably do better by using a calibrated mount (having azimuth and elevation scales) and the K-1 to set it up to true north. Then use a sky reference to translate to earth coordinates for your given time allowing the mount to be pointed very nearly at the object of interest. From there the astrotracer could acquire a shot. You might have to be careful with the mount so it wouldn't affect the magnetic calibration needed for the astrotracer (aluminum, carbon fiber, and most composites won't affect magnetic calibration).
Forum: Pentax Camera and Field Accessories 11-02-2018, 08:07 AM  
I have a Manfrotto monopod
Posted By Bob 256
Replies: 17
Views: 637
You might want to check Home Depot or your local hardware store. My Manfrotto has a simple crutch tip for the foot and you might be able to find one that will fit your monopod if that's what you're looking for. Otherwise, the comment to check with B&H is spot on. They are quite helpful and would be sure to have it.
Forum: Film Processing, Scanning, and Darkroom 10-31-2018, 02:01 PM  
GAF Anscochrome developing?
Posted By Bob 256
Replies: 10
Views: 483
You really can't answer that question until you do some test shots. If you used the original Anscochrome developer, you would use the Anscochrome time listed in a previous post (12 min), but with a different developer, it's hard to predict exactly what the development time should be. Using recommended development time for the developer chosen (for a similar speed film) would probably get you close.

Emulsion, developer, processing time, and temperature all interact to form the final image so there are too many variables involved to get precise results without experimenting.

Here's a first developer formula for processing GAF films at 80 degrees F. - processing time 8 1/2 minutes

Metol 2.8 grams
Sodium sulfite, des 50 grams
Hydroquinone 6 grams
Sodium Metaborate, crystals 45 grams
Trisodium Phosphate crystals 4 grams
Potassium Bromide 2 grams
Potassium Iodide 1% solution 1 cc
Sodium Thiocyanate 2 grams
6-nitrobenzimidazole nitrate 0.2% solution 20cc
Water to make 1 liter

Be careful since the emulsion will soften quite a bit at 80 degrees.
Forum: Pentax K-1 10-31-2018, 09:08 AM  
New territory for me Panoramic shot needed
Posted By Bob 256
Replies: 12
Views: 658
Your only solution with the K-1 is to take a large series of individual shots (covering a projected sphere) and stitch them with software. Creating an alpha channel would also be done in software. It would best be done with a longer lens such that the field of each shot is limited so less edge distortion results and stitching is simplified but will be a tradeoff between focal length and how many shots you need to take. As for eliminating a "tripod", the support for the camera would have to be articulated and moved between shots so as not to show in the stitched result. Your format doesn't make sense since 2048x1024 implies a rectangular frame - not a spherical one. In any case, the resolution would be determined after stitching and by the software used to develop the spherical format.

As mentioned, it might be easier to use a spherical camera and combine two or more frames into a single 360 degree spherical shot.

Not an easy task and not suited for scenes with motion involved. Special cameras have been developed to capture a single shot 360 degree spherical image, but they are special, and usually involve two fisheye type cameras with more than 180 degree coverage, pointing in opposite directions, and even then, the support will show in the image and will have to be removed via software.
Forum: Pentax SLR Lens Discussion 10-30-2018, 07:37 AM  
Left lenses in basement for two day-what should I do
Posted By Bob 256
Replies: 18
Views: 1,670
As robgski mentioned, it's a good idea to keep a small packet of desiccant in your lens case with a lens. I use the kind with an indicator which goes from orange to green when it has had its limit of moisture (then you throw them in a 250 degree F oven to restore their moisture absorption). Check ebay for lots of options. There are large and small packets so don't buy a humongus packet size for your lens case (maybe more appropriate for a camera).

I think your original question has been thoroughly answered - no anti acid needed (for your stomach).
Forum: Troubleshooting and Beginner Help 10-28-2018, 01:31 PM  
O-GPS Not Turning On
Posted By Bob 256
Replies: 6
Views: 580
The fact that the batteries leaked shouldn't have fried anything but leaking batteries these days can be a sign that something in the circuit shorted and placed a load on the batteries causing them to leak. If it was just leaking batteries, cleaning up the mess and making sure the new batteries make contact (clean the battery terminals that came into contact with the leak really well), the unit should work again.

It's probably time to get it to a service center and have them take a look. It can be hard to diagnose your issue by e-mail and a look-see by someone familiar with your unit would be worthwhile.
Forum: Film Processing, Scanning, and Darkroom 10-27-2018, 07:33 PM  
Light box for film viewing
Posted By Bob 256
Replies: 16
Views: 787
More important than the Kelvin rating is the Color Rendering Index. Fortunately most LED sources now have CRIs that are pretty high (near 90 percent - true daylight has a CRI of 100%). Just avoid any sources that have CRIs below 75. The problem is that some colors can shift when viewed with low CRI sources, relative to what they should be. Many older florescent lighted boxes had issues because of this (florescent sources can have particularly bad CRIs).

Your eye adapts to Kelvin temperature much like auto-white level in a camera, so the actual K value is less important though if you are viewing slides in a low K environment (incandescent lighting), a high K (5000) light box might make slides look on the bluish side. Usually, however, a 3000 to 5000 K source works fine.
Forum: Film Processing, Scanning, and Darkroom 10-25-2018, 02:24 PM  
GAF Anscochrome developing?
Posted By Bob 256
Replies: 10
Views: 483
For B&W, just develop as you would any B&W film (develop, stop-bath, fix, & wash). Here's a link that describes removing the rem-jet backing.

Removal of Rem-jet backing from Cine Film Lomography.

You might need to adjust your development times depending on exposure and developer used. Good luck.
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