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Forum: Troubleshooting and Beginner Help 09-10-2021, 11:55 AM  
K-3 hotshoe - can I glue it?
Posted By Philoslothical
Replies: 28
Views: 1,571
This might be a dumb idea, and there might be things I haven't considered (I shoot macro and smaller, nothing involving people). What about a wearable flash, like on the brim of a hat or potentially perched on your shoulder with a strap, with a wireless trigger that would be activated by transmitters equipped on each of your cameras. As long as the transmitters and trigger are all on the same channel you should be able to effectively share one flash between them. You'd have to turn towards your shots differently, and it might mess up your stance, but it might be an interesting experiment.
Forum: Pentax DSLR Discussion 09-09-2021, 09:31 AM  
Trouble with using Pentax Auto Extension Tubes
Posted By Philoslothical
Replies: 16
Views: 1,197
I misremembered and corrected my comment above. It's been quite a while. I also remember having to sand the black anodizing off a portion of one of my tubes to short the camera's contacts in order to get it to work properly. I used a fine silica sandpaper for it and had no issues, but the tube needs to be cleaned well after or you could have a black dust invasion.
Forum: Pentax DSLR Discussion 09-09-2021, 08:25 AM  
Trouble with using Pentax Auto Extension Tubes
Posted By Philoslothical
Replies: 16
Views: 1,197
Sure you do, perhaps just not a new new lens. If you can afford tubes you can squeak something to use on them until you can get something better. All you need is a little prime lens, like one of the older 50mm. For the first several years I shot macro I was using a set of tubes like you have with a Pentax A 50mm f./2, which was a kit lens on some old film cameras. It cost about $20 for the lens, and you should have no trouble finding one around that price. It's not the sharpest 50mm lens out there, and you'll get better quality if you can spend ~$100 on a Pentax F 50mm f./1.7, but it will allow you to learn to shoot macro in the meantime, and then when you have an opportunity for a better lens sometime in the future, you'll see the quality jump in your work. You'll already know what you're doing so you'll be able to fully leverage the new lens.

Be sure to get a prime that has an aperture ring. Keep the aperture ring set to the aperture you want to use while using the tubes. A lens lacking an aperture ring will only shoot wide open on tubes, which isn't useful.

I understand your disappointment, but you don't want to use extension tubes with zoom lenses, anyway. Some zoom lenses won't work at all with tubes. Due to the design of their optics, when you add extension the focal point can be reduced to being inside the front element of the lens, making focusing on a subject impossible. Zoom lenses with extension will also show more distortion, as a rule, because they're not designed to have the same resolving power as a decent prime. Extension exaggerates any flaws present in the optics of a lens.

This thread helped me get started a decade ago, and it's still entirely relevant. It's a good read. Don't get discouraged. You have so much good stuff ahead of you if you pursue this.

Edit to add: My Pentax A 50mm f./2 is pretty beat up, the coatings are a bit messy, but if it's of use to you and you're willing to cover the shipping I'll send it to you at no additional cost. I'm located in Canada. And edited again to correct a misremembered point.
Forum: Post Your Photos! 08-19-2021, 09:55 PM  
Abstract Snakes, Fish and Water
Posted By Philoslothical
Replies: 18
Views: 742
The lower left quadrant of that photo would make an interesting crop. I love the shots; it's just a suggestion. Thanks for sharing.

The water snakes here in Ontario can be quite aggressive. When I was a kid I had one chase my canoe, and other times I've had them rush at me when I've surprised them along the shores of lakes. They're relatively harmless, non-venomous as you said, but I still wouldn't want a bite from one.
Forum: Post Your Photos! 08-19-2021, 08:20 PM  
Macro Red Admiral Details
Posted By Philoslothical
Replies: 2
Views: 389
These are highlights from a set I recently shot of a Red Admiral butterfly. I collected it dead along a local roadside, and this is how I've sourced almost all of my insect specimens in recent years. They're focus stacked composites, each containing several hundred exposures. The magnification is 23.5X, and the horizontal field of view is approximately 1mm. Some of them are slightly cropped, but most of these use most of the available frame so you can compare the relative size of the different types of scales, or at least get an idea of it. I shot them with continuous light from a pair of LED floodlights positioned next to my microscope's stage.

The full set is on this page. I selected from it for this post, but there are quite a few more there if you enjoy these.









The Red Admiral, Vanessa atalanta has a truly incredible diversity of wing and body scales compared to many other species I've examined. The undersides of their wings appear to have finely mottled patterns of greys, taupe, and black, but on closer examination those soft Earth tones are comprised of purple and red and metallic gold scales, like you can see below. Vanessa cardui, commonly known as the Painted Lady butterfly has a similar richness of colour and micro-morphology. There are few butterflies I enjoy more on these scales.

Forum: Troubleshooting and Beginner Help 08-19-2021, 07:12 PM  
Focus confirmation with mf lens
Posted By Philoslothical
Replies: 19
Views: 3,439
I find back button focusing to be more effective. There's no concern of accidentally squeezing off a shot early. I changed it to this years ago and never looked back; it's a good tip. Keep in mind that we still wake up the meter with a half press, so it doesn't obviate using it entirely.

You shouldn't need any contacts present or exposed between the camera and lens to get the AF beep. The camera needs to be set in the AF mode you want to use, but it should work with anything in that state.

To use an AF lens manually while still using the AF confirmation beep you could try taping the data contact - or all of the contacts - between your lens and camera. I use electrical tape for this. You will lose the functionality relating to the pins you insulate, but if you can live without those aspects it will provide the beep while disabling the AF drive.

If in future you want to short contacts while using a black anodized lens mount, another method is to gently sand the anodizing off with a fine silica sandpaper. I'd do this well away from my other kit, and I scrupulously cleaned my extension tubes when I did it to them, worrying about dust. It's a permanent solution and it reduces the possibility of a bit of tin foil or some other conductor finding its way into your camera.

I've been thinking about this AF issue recently from another angle. If a person asked me if I use AF, and I am using the AF confirmation with a manual lens, am I still using AF? I do this a lot with my Irix macro lens. It works really well for stuff like butterflies. I'd have to say yes, I'm still using AF, but I guess it depends on how heavily I choose to rely on it.
Forum: Mini-Challenges, Games, and Photo Stories 08-19-2021, 05:27 PM  
Thematic Show your texture, pattern, repetition, shape etc. shots here!
Posted By Philoslothical
Replies: 4,173
Views: 323,222


Mourning Cloak butterfly scales from the creamy outer margin of its wing. It's a stack of several hundred exposures shot at ~23X magnification. The horizontal field of view is approximately 1mm.
Forum: Pentax K-3 III 08-18-2021, 09:20 PM  
K3 iii Live view and focus peaking compared to K3
Posted By Philoslothical
Replies: 17
Views: 3,113
No worries. I appreciate all of the other information you've provided in this thread. It's been very helpful.
Forum: Pentax K-3 III 08-17-2021, 02:09 PM  
K3 iii Live view and focus peaking compared to K3
Posted By Philoslothical
Replies: 17
Views: 3,113
This is promising, thank you for looking into this for me! It should be on the K-3, too. I just searched the manuals and checked my camera's menu for the nth time, and it's not, but it's something to know they corrected the oversight eventually.

Does the K-3 iii handle memory cards any more intelligently than the K-3? This is the other biggie for me. If I use slot 2 at all I have to manually remove it and power cycle the camera twice (card out, card back in) to get it to use slot 1 again. If I start using slot 2 and card 1 is empty, it won't switch to card 1 after card 2 fills up, it just decides the camera is full because slot 2 comes after slot 1. I really question the people who let this feature go to market in this state. One would think it could have been corrected in a firmware update, though this is true of the "LV simulation" setting, too.
Forum: Pentax K-3 III 08-16-2021, 07:17 AM  
K3 iii Live view and focus peaking compared to K3
Posted By Philoslothical
Replies: 17
Views: 3,113
The way the K-3 simulates exposure in Live View is the thing I hate most about my camera - well, the fact that it can't be turned off. I'd be very interested to know if Pentax has improved on this in models newer than the K-3, such as your K-3 iii.

The problem is that with an A series or newer lens attached, when using Live View the camera attempts to simulate the exposure you will get on the screen. This makes it impossible for me to focus efficiently in dim environments while using a flash for illumination. I have to adjust one of the exposure factors, like the shutter speed, to brighten the display enough to see what I'm doing, and then I have to crank it back down to actually take the shot. It's a lot of extra work and it results in missing or not taking shots.

I recently got this K-3 and I think it may be my last Pentax camera. I'm coming from a K-7, and I also used a K-r for years, and I've used a K-5. I have a K-x kicking around, too. So I'm familiar with that generation of cameras and they all consistently lit the Live View display regardless of the actual exposure. This was simulated, too, I would assume by boosting the ISO, just turning up the gain, so to speak. It bothers me that Pentax failed to include a setting to turn off their "improvement" for something that affects such basic functionality.

For now, I've taped the contacts on my lens, and this works. It shows the K-3 is capable of using the "old way" of displaying Live View, but it prevents the possibility of using AF. Fortunately I don't need AF for my niche, but it's a severe limitation of the workaround. Please tell me it gets better in more modern cameras.
Forum: Pentax K-3 & K-3 II 08-15-2021, 12:48 AM  
Problems using battery grip D-BG5
Posted By Philoslothical
Replies: 15
Views: 2,867
Kinda. It will switch from card 1 to card 2, but it won't switch from card 2 to card 1. :( I do focus stacking, and if the camera is using slot 2 and card 2 fills up, the K-3 is not smart enough to switch to slot and card 1, even if card 1 is empty. If I fill my camera it means I finish my shoot with slot 2 active. If I don't remember to do the "fix" I'm about to describe for you, I'll get halfway through a shoot and unable to use card 1 at all until I do it. There is no setting or button to select which card to use.

What you have to do is turn off the camera, open the card cover and remove the card from slot 2, close the cover and turn on the camera. Next, turn off the camera, open it up again, replace the card in slot 2, and turn the camera back on. Now your K-3 is ready to use slot 1 again. You'll have to do this after every time you use slot 2.

If I sound a bit salty about this, it's because I am. Between this, the issue with the grip, and the horrible simulated "auto-gain" feature in Live View that can't be turned off, I'm for the first time since I started asking myself if my next camera will be Pentax.
Forum: Post Your Photos! 07-27-2021, 08:54 PM  
Macro Tiger Swallowtail Details Part 2 (of 2)
Posted By Philoslothical
Replies: 16
Views: 619
Looks good to me! I bet the fine focus on it is awesome. A few thoughts...

You're right that the condenser won't be useful for reflected light work, but it's not a bad thing that it's there. Sometimes I use it for backlighting thin specimens. Most of the time you can just ignore it and use whatever LED lights you decide to set up pointed at the stage.

The two oil immersion objectives won't be useful for this stuff either (obviously), but this way you have two ports to fill with hand picked objectives better suited to photography, and there is a wide variety available for all budgets. Be sure to check the thread diameter your microscope accepts before shopping. I've seen plenty of adapters available for smaller objectives, like to mount an m25 in an m26 turret, so that's a possibility, too. I can't tell by looking which size yours uses. When mixing or adapting objectives you also need to consider the tube distance they need, if they're not "infinity" objectives.

You might want to get a different eyepiece for photography, too, because it's quite possible that yours are old enough to have become hazy, and because there are probably eyepieces better suited, with wider fields of view. There are also ocular eyepieces designed specifically for photography but they're less common.

Last thing, the angle of the eyepieces doesn't look too severe, it's nearly vertical. I think this will put less stress on your camera mount and/or filter thread than one that's more horizontal. If it can be adjusted, use it as close to vertical as possible.

And off on a tangent, it strikes me that the people who designed and built this microscope had no inkling that anybody might even be able to do focus stacking in the future. It's crazy how fast we progressed technologically, but it's a testament to their design that good microscopes routinely outlive us in their usefulness. Thanks for your comments. There's nothing here more pleasing to me than when I see people taking a greater interest in this stuff, because I enjoy it so much.
Forum: Post Your Photos! 07-26-2021, 10:16 PM  
Nature I saw a ghost!?
Posted By Philoslothical
Replies: 9
Views: 386
Indian pipes are awesome. They must be having a particularly good year. I found some this past week, too. They were spawned by the heavy rainstorms we had, along with a host of other fungi.

My weak understanding is that they interface with the fungus, and this allows them to convey nutrients from the wood both species are parasitizing. They're definitely a plant rather than a fungus, although they're not dependent on light as they don't produce chlorophyll, so they can grow in little nooks under fallen trees that get very little light.

Good shot, and I love your enthusiasm for them.
Forum: Post Your Photos! 07-26-2021, 07:55 PM  
Macro recent macro shots 4
Posted By Philoslothical
Replies: 18
Views: 775
That water droplet shot is intense! I love the colours and the composition. You've got some very nice soft gradient backgrounds in your shots. On this scale it's about composition as much as depth of field; selecting the best distance of your background from the macro subject to get the effect. Well done.

Edit, and while I like both, I like the wider version above better than the tighter crop. Just personal preference. That blaze of bright red is very appealing.
Forum: Pentax DSLR Discussion 07-26-2021, 07:45 PM  
More reach on APS-c demonstrated
Posted By Philoslothical
Replies: 106
Views: 7,686
I'd suggest you look in the forks and crotches of small trees around the edges of open areas. The few times I've found them it's always been in a small tree or tree-like shrub in a field with other structure, or near its edge. Sometimes they do use branches though, so it's not a rule. They're beautiful little expressions of engineering, the way they craft them. I'm not sure what stage they'd be at right now where you are, but there's also the possibility of catching a nest occupied, so it might be a good time to go on a little hunt. The nests I've found had been abandoned. I always watch for stuff like this while hiking but they're very rare to actually find.
Forum: Pentax DSLR Discussion 07-26-2021, 07:27 PM  
More reach on APS-c demonstrated
Posted By Philoslothical
Replies: 106
Views: 7,686
I'm learning all about the struggle with my Irix 150mm. I get some of my shots. I think my hit rate has improved because I'm taking fewer, more methodical shots. It's a good thing. She's a beauty, too, your hummingbird there. Lovely animals. They build their nests from lichens and spiderwebs, among other things. They do this because of the antimicrobial properties of the materials, and spider silk is probably pretty soft, too. If you ever find one of their nests around, it would make a lovely subject we seldom see posted.
Forum: Post Your Photos! 07-26-2021, 06:29 PM  
Macro Tiger Swallowtail Details Part 2 (of 2)
Posted By Philoslothical
Replies: 16
Views: 619
It sounds like a wonderful microscope. I'd love to see a picture of it. You should absolutely do this. Try all kinds of stuff. There are few hard and fast rules. For reflected light you can just mount bright LEDs of whatever type appeals to you (by colour temperature and brightness, angle of beam, etc) on either side of the stage and then optionally add a little diffuser around the subject. I only got my strobes recently, and until then I did all of my stuff with the same two LED flood lights, about $8 each, just brought in as close to the stage as possible. The scatter from them results in plenty of diffuse light for most things, and for stuff like glassy bug eyes I can improvise various diffusers to cut the glare. So it is feasible to get into this stuff with virtually no additional investment, or very slight, since you have a good microscope and camera. I wish you lots of luck with it!
Forum: Post Your Photos! 07-26-2021, 05:21 PM  
Macro Tiger Swallowtail Details Part 2 (of 2)
Posted By Philoslothical
Replies: 16
Views: 619
Thanks for the feedback! I got into this stuff because it's the only way I could see it, and seeing it helped me to accept the reality of my own predicament on grander scales over time.



It sounds like a very similar technique, and you could use that K-5 to do fluorescence microscopy, too. I'd suggest you look up some photos of it, as you could make some really striking stuff that way if it appeals to you.

Used microscopes are not crazy expensive, or at least there are many good, affordable new and used options, so if you get into it you might find you want to expand beyond the binocular. If it's a continuous zoom like mine, you may find it a bit restrictive in terms of magnification. Mine also doesn't play well with an eyepiece in the trinocular port, and I think it's a matter of correcting the amount of extension I use, but I haven't figured it out yet. What I'm driving at is a cheap compound microscope would let you do far more, but that's no reason to neglect the binocular scope you have, either. I use both of mine, but I use the compound microscope much more. I'm happy to help with what info I can, and I hope you have fun with it!



It's amazing what can be done with electron microscopes. It's definitely something I'd have enjoyed the opportunity to try. Thanks.
Forum: Pentax DSLR Discussion 07-26-2021, 04:33 PM  
More reach on APS-c demonstrated
Posted By Philoslothical
Replies: 106
Views: 7,686
The detail on those throat feathers is remarkable. Gorgeous photos for a test. I think in your position I'd try to compose an angle that omits the feeder, and then get as many shots of them as I could while they're around.

You demonstrated the principle well, too.
Forum: Mini-Challenges, Games, and Photo Stories 07-26-2021, 04:14 PM  
Thematic Show me your insects
Posted By Philoslothical
Replies: 6,692
Views: 516,697
I think you're right. If the idea ever gets past the daydream stage I'll keep that in mind. Thanks.
Forum: Mini-Challenges, Games, and Photo Stories 07-26-2021, 03:57 PM  
Thematic Show me your insects
Posted By Philoslothical
Replies: 6,692
Views: 516,697
Beautiful shot! It's rare to find them with their eyes completely clean, so don't worry about that. I had no idea they enjoyed molasses, but it makes sense, and it's a great idea for non-destructively immobilizing them, at least briefly.

Sometimes I entertain daydreams about building a macro rig inside one of those portable coolers... So I could haul the thing into the field and then chill bugs right on the stage, and then let them go after. I think the condensation issue could be beaten by physically isolating the camera and coating the exposed lens or objective with one of those anti-fogging sprays.
Forum: Post Your Photos! 07-26-2021, 03:15 PM  
Macro Tiger Swallowtail Details Part 2 (of 2)
Posted By Philoslothical
Replies: 16
Views: 619
Here you go. It is what it is, which isn't much, but it works. In the background you can see my continuous zoom microscope, which I use for lower magnification stuff like my bug "portraits" and for finding subjects on specimens. The compound microscope is better suited to stacking as it has a fine focus wheel, and a nice one, considering. I move the strobes around as appropriate for my subject. They're new to me, and I'm still experimenting. Out of frame at the top there's a cord running across that I clip my camera strap to, to keep it out of the way but loose enough it can move with the microscope head, and also to reduce the clutter from the AC adapter cord. If you have questions I'll do my best to help.







Thanks! I'm pleased people are enjoying them. Reactions vary widely, some people think they're really gross. :lol:

An SEM would be fun to play with...
Forum: Product Suggestions and Feedback 07-25-2021, 08:28 PM  
Focus review mode?
Posted By Philoslothical
Replies: 4
Views: 859
And/or make it animate. If it blinked it would be much more distinctive, but I agree it would be so much better if we could set a colour value for it, because the visibility sucks on white or nearly white subjects and as you say, it's not visible enough in bright conditions.

If it had a mode to make sharp pixels blink in their inverse colour value I bet it would solve the problem. So green leaves would highlight with pink/magenta, for example. I think this combined with animating it would make it visible enough anytime.

I guess the use case I'm thinking for handheld stuff is when I have time to glance at the instant review to see if I got the shot, but I don't have time to go into playback mode, zoom in, pan around, and then try the shot again if I missed. Like this afternoon, with the hummingbird moths. Over and over and over again. They're so incredibly fast, especially for manual focus, but I have found that after a shot I can just kind of tilt my camera away to glimpse the screen without fully lowering it, and if I had a good indicator of what was sharp in the frame I think I could improve much more rapidly.
Forum: Product Suggestions and Feedback 07-25-2021, 06:50 PM  
Focus review mode?
Posted By Philoslothical
Replies: 4
Views: 859
I just recently upgraded to a K-3, and it's my first taste of focus peaking. I like it, but I rarely shoot in Live View for prolonged periods. I realized what I'd really like is the same concept applied to the instant review and playback modes. Technically it should be easier to scan a still image than the live feed from the sensor. I want a focus review mode that will make the sharp pixels in photos I've already taken blink on and off, like a highlight or shadow clipping warning. This would be extremely useful to me, as I do focus stacking, but I could see it also being very useful in the field when conditions may be too bright to make out the fine details on our camera displays while chimping.

I'm just curious if anybody else agrees, or has some reason why it couldn't work, or other ideas that might improve the concept further?
Forum: Post Your Photos! 07-25-2021, 06:35 PM  
Macro Tiger Swallowtail Details Part 2 (of 2)
Posted By Philoslothical
Replies: 16
Views: 619
Thanks for such nice feedback! It baffles me that their tiny brains can so gracefully control all of their complexity.



Thanks, and I have some fairly poor photos of my setup but I think I'll shoot some new ones tonight, and I'll add one here tomorrow. I'm doing eyepiece projection photomicroscopy, which is a fancy way of saying I'm adapting my camera with a lens attached directly onto the eyepiece of the microscope. This way the magnification is fairly consistent with what we see with our eyes when looking through the eyepiece, but it depends on the focal length of the "host lens". I use the 50mm f./1.7 because it's what I have and it increases the magnification slightly on the APS-C sensor.

For lighting I'm experimenting with strobes. It seems to have been a decent idea, at least for some subjects, but I'm still in the process of experimenting with making diffusers and trying different things. Prior to that, and still as a supplement for composing the shot I've been using a pair of ordinary LED floodlights in desk lamps, as close to the stage as I can get them. I do my composing in Live View, and then I turn it off and shoot the stack while watching the opposite side of the focusing wheel to measure my increments more precisely. I've had a much easier time training the muscle memory for it while watching my hand do it, so I'd suggest trying that if you get into manual stacking. I monitor progress and decide when to stop by watching the 1 second reviews of the exposures. This stuff is a lot of fun, and I absolutely recommend it. Over the past two years I've put thousands of happy hours into it, but you don't have to do that to get results. It's just very addictive to me.

One concern with binocular microscopes is that you need to be sure it can support the weight of your camera at an angle, and it does put some strain on your camera mount, and potentially the filter thread, but I don't think it should be a problem unless you're using something quite heavy. You'll just want to be gentle with it while it's mounted. There's an example of an adapter similar to the one I use on Ebay here that is probably all you need to mount a camera and lens, attaching the adapter to the filter thread of whichever lens you decide to use. If you can find one that has rubber tipped screws, even better, because it might scuff your eyepiece otherwise. You could also improvise. A bit of electrical tape on the eyepiece first should protect the finish from the screws. You might also want to look for one with longer screws so you could use it with a 23mm eyepiece in future. I use some PVC tape to prevent light leaks, and I keep the adapter and the prime lens mounted on that microscope all of the time. This way I can just swap the body off. It's very convenient.



Thanks! I was a little concerned I was posting too many lately, prior to posting.
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