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Old August 22nd, 2019, 05:26 PM   #76
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Re: My lens has a spot on it, is there anything I can do?

Well it depends. Someone said I should buy a video camera with a permanently built on lens because since I could use a new camera soon anyway, it would save money to buy a camera with a telephoto lens build onto a compared to buy OnePlus a separate telephoto lens. Are there any disadvantages to a video camera with just one telephoto lens built on though?
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Old August 22nd, 2019, 05:42 PM   #77
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Re: My lens has a spot on it, is there anything I can do?

First one that comes to mind is a video camera like that probably wont have the shallow depth of field look all the filmmakers love.
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Old August 22nd, 2019, 06:15 PM   #78
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Re: My lens has a spot on it, is there anything I can do?

Quote:
Originally Posted by Josh Bass View Post
First one that comes to mind is a video camera like that probably wont have the shallow depth of field look all the filmmakers love.
I think what someone was suggesting you could buy a decent eng semi-pro camera for less than a professional superzoom lens. Prosumer camcorders typically have a 24-600mm built in lens and would work well for wildlife shooting in bright conditions where you don’t want a super shallow dof either. For versatility you can’t beat a camcorder: run gun, interviews, event work, etc. The quickly becoming standard is 1” sensor, isn’t going give you that cinema style shallow dof, but no camera can do everything.

I am by no means knocking the pro super telephoto lenses but no one in their right mind is buying them and offering their services for free. It also wouldn’t make sense using such a lens on a out dated consumer dslr.
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Old August 22nd, 2019, 07:59 PM   #79
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Re: My lens has a spot on it, is there anything I can do?

Yeah that was another thing I didn't like about camcorders either, but it seems that lately some videocameras have the built in zoom lens, but have larger sensors now for a shallow DOF. Is there any with a APS-C size sensor for example with a zoom lens that can go up to at least 400mm? Cause APS-C has quite a bit of shallow DOF, if the lens can open wide for it.
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Old August 23rd, 2019, 01:16 AM   #80
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Re: My lens has a spot on it, is there anything I can do?

You'll find that some camcorders with built in zooms can produce broadcast standard video, which only very few DSLRS can do. With long focal length lenses you get a shallow DOF anyway.

Once you're into large sensor cameras, you won't find long focal length lenses coming as built in zooms, the laws of physics will be working against you. The f 4 25mm to 250mm cine 35mm lens is a large lens, your DSLR would be much smaller than its matte box.

With builtin zooms. you have the issue of not being able to put focus marks on the focus ring. See your thread on the subject.

Note that "24-600mm" is the equivalent focal length, not the actual one on the camcorders.

Before we end up going around in circles, are you planing to buy a new lens for this wildlife film or going to find ways to hide your spot in the clutter of the undergrowth or fix it in post when you notice it?

If you're going to buy one, is it the plan to use it on your drama films?

If you are, I would check out your thread on fly by wire focusing again, to avoid going over old ground again.
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Old August 23rd, 2019, 07:01 AM   #81
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Re: My lens has a spot on it, is there anything I can do?

Yep I want to buy a new lens to use on drama films as well, not just this one. I might have to use the current lens on the wildlife one, since I am not sure which one to buy.

That's true, about wanting to set focus marks, I would want a telephoto lens that can do that.

I suppose I could get the Tamron 100-400, and forget about the fixed aperture. I understand it's not fly-by-wire and has a mechanical focus, but is that lens sharp enough to look professional, when zoomed all the way?
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Old August 23rd, 2019, 07:27 AM   #82
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Re: My lens has a spot on it, is there anything I can do?

Quickly looking at a review the Tamron seems OK, the aperture ramping shouldn't be an issue once you've closed down a stop or so. You may find the focus ring moves continuously, although there's a scale inside the window, there's no infinity stop, so how well it repeats its position on the scale would need to be tested. https://www.kenrockwell.com/tamron/100-400mm.htm
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Old August 23rd, 2019, 07:33 AM   #83
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Re: My lens has a spot on it, is there anything I can do?

Oh okay, are you saying that it has no 'hard stop' or no infinity marking? Cause I looked at some lenses at the store, and the person at the store said it had a hard stop, unless I'm remembering wrong.

As for ramping, yeah the current lens I have now, the aperture ramps at any aperture setting. Here's a test I did at f8:


But will the Tamron not have aperture ramping at more closed apertures like that, you mean?
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Old August 23rd, 2019, 08:15 AM   #84
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Re: My lens has a spot on it, is there anything I can do?

A hard stop usually means that focus ring stops at or commonly just after the infinity marking on the scale.

Usually aperture ramping is caused by the outside of the lens being a small a diameter for the longer focal lengths, so it's acting like a stop aperture until it matches the stop being used on the lens' own internal iris, It's like that to keep the lens sizes down, constant aperture lens are larger in order to avoid this happening,

I suspect you wont be able to avoid it with many stills lenses.
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Old August 23rd, 2019, 02:44 PM   #85
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Re: My lens has a spot on it, is there anything I can do?

Oh ok. Well it was suggested to me before to get a lens like rokinon since they are made for video but does anyone make lenses like that that are telephoto zoom lenses though?
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Old August 23rd, 2019, 05:25 PM   #86
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Re: My lens has a spot on it, is there anything I can do?

Rokinon only have a mirror lens, which has a fixed aperture, so limited for video. https://www.rokinon.com/lenses/digit...300mm-f63-dslr

Test the Tamron out at your local shop to see if it works as required for the focus. It may overshoot the infinity mark, which.isn't a problem. It looks OK in this video, but you should test yourself to ensure that the focus ring doesn't go round endlessly.


Your options are limited by your budget, but it looks a possibly, Don't expect this to act as a parfocal zoom, but you're less likely to zoom in shot with these longer focal length.
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Old August 23rd, 2019, 09:12 PM   #87
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Re: My lens has a spot on it, is there anything I can do?

Okay thanks. I was going to do that as well. However, the store said that my current lens was still under warranty, so they may be able to do something about that black spot on it after all.

I'd still want a lens without a fly-by-wire focus system though, if that is what is needed for competent focus pulling though.
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Old August 23rd, 2019, 09:36 PM   #88
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Re: My lens has a spot on it, is there anything I can do?

What you need for competent focus pulling is an experienced 1st AC.
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Old August 23rd, 2019, 09:52 PM   #89
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Re: My lens has a spot on it, is there anything I can do?

Yep for sure I want that, and plan to get it. But even an AC will want a mechanical focus though too right?
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Old August 23rd, 2019, 10:23 PM   #90
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Re: My lens has a spot on it, is there anything I can do?

If they're worth their salt, an AC will be expecting to work with a proper *cinema* lens, such as the Canon Cinema EOS CN-E30-300mm T2.95-3.7 L SP -- which costs $45,000, so you rent it, you don't buy it. But now we're talking in circles again.

Here's the B&H link for the Roki 300mm Reflex (in Canon EF) that was mentioned earlier. $270. You get what you pay for.
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