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Nature / Re: Unknown

« Last post by Shortsighted on July 07, 2025, 02:44:51 PM »

Quite right. A telephoto section of a cloud of gnats ... shot into the sun @ 1/15 sec ... with a dark background. I should have spent more time taking some photos, playing around with this observation, but I didn't think much of a swirling cloud of gnats at the time. Bottom line, ... I didn't think even as deeply as those gnats.

Nature / Re: Unknown

« Last post by Dr. John on July 07, 2025, 12:09:03 PM »

Insects with a longer exposure?

Equipment and Technique / Re: To TC or not to TC? That is the question.

« Last post by Shortsighted on July 05, 2025, 06:01:47 PM »

I previously posited the question whether there was much to be gained by coupling a teleconverter onto a telephoto lens to create a longer focal length collaboration. The boost in focal length is really just a trick to create the illusion of a longer focal length by magnifying the image cone as if it had been sent from an objective lens farther away. The magnifying elements within the TC also magnify any defects
present in the original image, including parent glass aberrations.

The idea is to project a bigger image onto the sensor so that the subject is defined by more pixels,
thereby offering the potential for more detail and fewer post-processing artifacts that start to show up
as the image is cropped to make up for telephoto shortfalls.

The thing is, does a TC cause significant deterioration of image quality (IQ) by an amount that might negate any benefit derived by putting more pixels on the subject? In other words, would a heavy crop of the parent image be worse than an uncropped image captured from a collaboration of a lens+TC? If the pixel density of the sensor is high enough, or if the sensor size (quality) is big enough then an image so taken should be game for considerable cropping in post. It doesn’t take much cropping to enlarge a pic taken with a 300mm lens to look like an uncropped pic taken with a 300mm + 1.4x TC = 420mm.

Of course, once a lens is coupled to 1.4x TC the resultant image always tends to be cropped as well because there never seems to be enough lens magnification to satisfy a bird photographer. My testing with that set-up has revealed that sometimes the cropped 300mm image is actually better than the less cropped 420mm image, while at other times the 420mm collaboration has the edge.

With a DSLR the slower AF implicit with using a TC might very likely be a deterrent as well. This issue might be moot when using a mirrorless camera with superior AF technology. If the TC collaboration exceeds the required f-stop of your camera body then its use is contraindicated. For example, an f6.3 lens coupled with a 1.4x TC would exceed the minimum speed needed to have a functioning AF system. Under those conditions the use of a TC means that manual focus is required and that unfortunate result is no longer acceptable in today’s world of auto-everything.

My DSLR can handle f8 if the AF is center-weighted so I decided to try a test by shooting a stationary subject across the street. I used both AF at 600mm, and then manual focus with a 1.4x TC. Then manual focus with a 2x TC. Then manual focus with a 2x TC + 1.4x TC. The resultant images were then cropped square to the same size. The longer focal length images were slightly boosted in brightness and contrast so that they would match the parent image in order to help mitigate scatter of light through the TC glass.

The subject was the wheel of a BMW parked across the street ... not mine, I can assure you. I only drive a Rolls. The distance was the street width, sidewalk and driveway length. The bottom line is that the cropped 600mm AF shot is the best. The 840mm (1.4x TC) may not have been focused well enough because the 1200mm (2x TC) is better. The two TCs mounted end-to-end to create 1640mm was not too bad either but trying to use that on a bird, while on a DSLR is a hopeless endeavour, unless it is a stationary satisfied duck in excellent light. Then again, if other bird photographers see you using daisy-chained TCs they might call the park authorities and have you escorted out. Birders have a code of conduct so I’m always trying to fly under the radar.

600mm f8

840mm f9 (1.4x TC) manual focus

1200mm f13 (2x TC) manual focus

1640mm f16 (1.4x TC plus 2x TC) manual focus

Nature / Unknown

« Last post by Shortsighted on July 04, 2025, 11:59:34 AM »

What do we have here?

Ontario Birds / Re: June 29th - Reesor (lower) Pond

« Last post by Shortsighted on July 04, 2025, 11:57:14 AM »

I decided to revisit Reesor (lower) Pond in the evening, thereby getting the light from a different compass point. Light from the west favoured the second nest. The chicks in that nest were much younger and I couldn't tell if there was only one chick, or two. The parent kingbird would sometimes rest on a stick emerging from the water, scanning for dragonflies which see better above and below them than they do straight ahead, which was perch-level. In one shot you can see a large dragonfly sticking out of the chick's open mouth.

Kingbird perched on stick not far above water-level

Can see the coronal red patch

Parent bird arrived with dragonfly

Dragonfly in chick's gaping mouth

Parent kingbird nestled on ... nest.

Equipment and Technique / Re: Firework Test of DJI Action 5 Pro - First-Time User Review

« Last post by Shortsighted on July 04, 2025, 11:44:21 AM »

Thanks. Yes, I did some research on it. If shooting at 30 fps then a shutter speed of twice that 'rate' is probably the way to go ... 1/60 sec shutter speed. Faster shutter speeds just reduces light and requires a faster frame rate, which could render the video a little brittle, fragmented motion and awkward.

Equipment and Technique / Re: Firework Test of DJI Action 5 Pro - First-Time User Review

« Last post by Charline on July 03, 2025, 08:46:42 PM »

When filming/photographing in Manual Mode, I often use auto ISO in a designated range.

The shutter speed can be set at an appropriate rate.

Equipment and Technique / Re: Firework Test of DJI Action 5 Pro - First-Time User Review

« Last post by Shortsighted on July 03, 2025, 03:21:49 PM »

When you say ISO 100 - 1600 ... does that mean the device selects the best ISO for the conditions within the set limits? In other words, does it self-set to 1600 under dark conditions and then decreases sensitivity when more light becomes available? Also, what does shutter speed mean when recording video? With film, the latency is 60 cycles/sec dictating frame rate, but how do you capture 1/30 sec exposures when that open-interval is too slow for the brain to see uninterrupted continuity? What does shutter speed even mean in video format?

Equipment and Technique / Re: Firework Test of DJI Action 5 Pro - First-Time User Review

« Last post by Charline on July 03, 2025, 02:17:42 PM »

My initial settings were based on the instructions from Gemini AI. Apparently Gemini AI did not know much about this camera and it keeps giving me the wrong info.

Chatgpt seems to know better.

I now know that I should have used ISO 100-1600 at least. The noise should be ok since I would not lighten the dark sky.

Also, the shutter speed 1/30 was too low. The camera has a good stablization feature since it is an action camera. But 1/30 was too slow.

Very little color-grading was applied since it is meant to be a test.

Equipment and Technique / Re: Firework Test of DJI Action 5 Pro - First-Time User Review

« Last post by Shortsighted on July 03, 2025, 01:37:44 PM »

I wish that I could offer you some constructive advise about this piece of kit but I'm entirely ignorant ... of video camera gear. The last adjustment was certainly the better setting. An ISO above 1600 in the city would likely show more light pollution based on still photography protocols. If it is a GoPro camera, wouldn't it be able to send the signal to a phone so that you could mount the camera on a hand-held boom, well above your head, and view your phone's screen to compose by turning, or tipping the boom as required, using image stabilization to control jitter? Everyone's raised cellphone is a little distracting. Just watching your video made me think someone bumped into me. I turned to look ... there's no one here.

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