canon – Why might my camera not charge and turn on?

The first thing to do is to check that your battery is actually charged(*). If the battery is old it may be dead (due to repeated self-discharge if you don’t use the camera much) and no amount of charging will give it life (at least in the camera, some external “intelligent” chargers have charging modes for near-dead batteries).

(*) using a multitester, but this assumes you can reach the battery contacts

minolta – How do I avoid losing images when my camera won’t rewind the exposed film?

  • Check your camera’s Owners Manual, User’s Manual, or Instruction Manual to see if there are any directions for this situation. Often they will be found in the “troubleshooting” section. If you don’t have a manual for your camera, you can usually find one online by googling your camera’s model name followed by the word manual. If there are instructions in the Manual, follow them. If there are not, proceed below.
  • Shut yourself into a totally dark room with absolutely no light in it. None. Zero. Zilch. This means a totally enclosed space with no windows or doors that aren’t sealed properly to eliminate all light from outside being allowed in. What may seem like a “totally dark” room to you when you first shut the door might be revealed to be otherwise once your vision has acclimated itself to the dark environment. The film in your camera needs no such acclimation time and will be fogged if exposed to any amount of light.¹
  • Open and close the camera’s back. If there is any light at all present, your film will be fogged! This might reset the camera’s counting mechanism. You need to be in a totally dark room with absolutely no light in it. None. Zero. Zilch. If this doesn’t do the trick, proceed below.
  • Most film cameras with an automatic film winder have a manual release mechanism somewhere. Typically it is a very small, recessed button on the bottom of the camera body. Press the button to release the tension on the takeup spool inside the camera.
  • Open the back of the camera. If there is any light at all present, your film will be fogged! You need to be in a totally dark room with absolutely no light in it. None. Zero. Zilch.
  • Gently remove the film cassette from the camera and wind the film into the cassette. The end with the smaller cylinder sticking up out of the film cassette should be turned counter-clockwise. You will probably need to turn it several times to take up any slack before the film will begin to move back into the film cassette. If you let go of the little button, the film inside the cassette may loosen up and you will need to take up the slack again. If there is any light at all present, your film will be fogged! You need to be in a totally dark room with absolutely no light in it. None. Zero. Zilch.
  • If the film has been properly released using the camera’s manual release button, it should roll off the takeup spool in the camera fairly easily. If there is any light at all present, your film will be fogged! You need to be in a totally dark room with absolutely no light in it. None. Zero. Zilch.
  • If you need to handle the film strip itself, try to do so touching only the edges of the back of the film (the side that is away from the camera’s shutter and light box as it runs through the camera). If there is any light at all present, your film will be fogged! You need to be in a totally dark room with absolutely no light in it. None. Zero. Zilch. Once the film has been developed you can clean the fingerprints off without damaging the image captured by the emulsion side of the film.
  • Wind the film completely into the cassette. If there is any light at all present, your film will be fogged! If you wish, you can leave a bit of the leader sticking out. Many people prefer not to leave any leader sticking out as this might cause them to later mistake the roll in question for an unexposed roll and shoot it again. You need to be in a totally dark room with absolutely no light in it. None. Zero. Zilch.
  • Once the film is rolled safely into the casette, you can turn the lights on or open the door to your totally dark room.

¹ There are some types of B&W film that are not sensitive to the far end of the visible spectrum in the near infrared range. For these, a very low power near infrared ‘safe light’ may be used for limited amounts of time. For undeveloped color film and most types of panchromatic B&W film, there is no such thing as a ‘safe light’ that will not fog your film.

Unity: How to get the visible bounds of an object, i.e. as it is seen from the camera?

Imagine you’d like to highlight a 3D GameObject by drawing a (translucent) UI panel above it. The UI panel should cover the object exactly. Therefore the object’s bounds, as it is seen from the camera, are needed.
How do you get these bounds? (In word space, or screen, viewport or canvas space, any way’s fine).

My problem is that (Collider|Renderer|Mesh).bounds does not take the camera’s position into account. Hence, depending on the camera’s location and the object’s dimensions, the bounds are more or less off.
Do you know how this can be fixed?

Any advise is very much appreciated. Thank you!

Recommendation for a budget camera for travel [closed]

I am looking for a travel camera for photos(will get a GoPro for video). My criteria is as follows:

  1. Price around $400
  2. Good picture quality for still photography (action shots would be great but most shots will be still shots of nature/views)
  3. Panorama feature
  4. Good in low light.

Any suggestions, please.

java – Parallax camera is not independent from the stage camera

I have a weird camera problem that I can’t solve! I add my actors to the main stage and use its camera too. Actors are constrained within the screen viewport.

I also have a second camera that I use for the parallax background. I check for touchDragged and touchDown to move the actor to that position. So I do:

public boolean touchDown(int screenX, int screenY, int pointer, int button) {
    getStage().getCamera().unproject(touchPosition.set(screenX, screenY, 0f));

    return false;

I can pan the parallax camera, and I do:

public void panBy(float x, float y)
    panTo.set((float)MathHelper.round(position.x + x, 0), (float)MathHelper.round(position.y + y, 0), 0);
    panning = true;

public void update() {
    if (panning) {
        position.x += (panTo.x - position.x) * panLerp;
        position.y += (panTo.y - position.y) * panLerp;

        Vector3 pos = new Vector3((float)MathHelper.round(position.x, 0), (float)MathHelper.round(position.y, 0), 0);

        if (pos.epsilonEquals(panTo)) {
            panning = false;


The drawing is done:

public void draw(Batch batch)
    //Start batch

    background.draw(batch, 1f);

    //End batch

Actors are handled by the stage right after the above draw call.

The above work fine individually. However when I pan and drag the actor the parallaxCamera follows the actor too. I the parallaxCamera to be totally independent and just keep scrolling.

Why do I have this behavior?

lens – Adapt Praktica MTL 5B lenses to Lumix G80 camera

I recently bought a Panasonic Lumix G80 12-60 mm/F3.5-5.6 kit lens as my first proper camera (apart from point and shoot cameras). I’ve also found some lenses that belonged to my dad, that were used on a Praktica MTL 5B film camera. The lenses are the following (click for higher res):

Praktica MTL 5B 50mm/F1.8 Kit Lens

Praktica MTL 5B 50mm/F1.8 Kit Lens

Sigma 70-210 mm/F4-5.6

Sigma 70-210 mm/F4-5.6

They were stored unused for around 20 years on a photographer’s bag, inside a closet in our home. They seem to be in good condition, no scratches on the glass (for what it’s worth, I’ve looked through the viewfinder and the image seemed fine), although the house is prone to humidity getting in so I don’t know if that could be an issue.

While I’ve studied quite a bit about digital photography, I’m very unexperienced about film/vintage stuff, so I hope someone could help me regarding these questions:

  1. Are there any adapters for this lenses to the L mount that are relatively cheap (less than 50€)?
  2. When adapted, what will be the actual Focal Lengths and Apertures in the M43 system?
  3. I’m aware that those lenses are manual focus only, but will I still get Zebras, Magnification and the likes?
  4. Is the quality of those lenses, after adapting, at least acceptable, or is not worth the investment/trouble?

root access – Is it possible to take pictures from both front and rear camera at the same time (like bothie)

There are apps that can do this but they are not exactly Bothie. The app allows the user to first take a picture from rear camera and then from the front camera (but not simultaneously). Nokia first came up with this idea in 2017.
More about Bothie

I am just wondering if this is a hardware feature or software. I can handle the software issue(with root) i think. And if this is not possible then can you please explain why and how it works?

Thanks a ton in advance : )

Home camera needed

I’m looking for a home camera. Any ideas what specifically I should be looking for? Maybe you own camera or alike? Appreciate!

c – Going in a direction, relative to the keys pressed and horizontal camera angle?

if you’re confused by some parts here, im just treating booleans as integers, 0 being false and 1 being true, but im wondering if theres a way to get rid of (X == 1 && Z == -1)*(float)M_PI, because for some reason without it everything else except for S and D at the same time would go the right direction, and that one’s to correct for that case only, but in general, i consider adding manual correctional statements instead of eliminating the root of the problem bad practive? how can i eliminate the root of the S and D going front and to the left instead of back and to the right diagonally, without needing a correctional statement?

const signed char Z = WKeyIsPressed-SKeyIsPressed, X = DKeyIsPressed-AKeyIsPressed;
if (Z || X) {
    const float Direction = (
           (HorizontalViewAngleRadians-(Z-1)*M_PI/2)*(Z != 0) // Calculate relative forward/backward movement
           (HorizontalViewAngleRadians-X*M_PI/2)*(X != 0) // Calculate relative left/right movement
       )/((Z&&X)+1) // Average the left/right and forward/backwards directions
       (X == 1 && Z == -1)*(float)M_PI; // Correct pressing S and D taking you the exact opposite direction it should
    XLocation -= sinf(Direction);
    ZLocation += cosf(Direction);

Nikon Camera: Installing previous firmware version

My Nikon Z6 has been away for major repairs, including a new PCB.
It is apparently coming back with a new firmware update (3.12) installed.

Two questions:

  1. My saved settings for the camera (NCSET002.BIN) were made in the previous firmware (3.11). Can I still load this file into the camera which now has the new firmware?
  2. If not, can re-install firmware 3.11 to replace 3.12?